I don't think I made myself very clear. In the new package, I only left what was necessary regarding the Daycare. The other career info I took out i.e. Stylist, Firefighter, etc. I made it into an override package. I will show you. I'm not very good at explaining things. Sorry.
It works in my game. I just tested it.

<?xml version="1.0"?>
<ActiveCareers>
<ActiveCareers>
<SKU>EP2</SKU>
<ActiveCareer></ActiveCareer>
<AgeFlags>48</AgeFlags>
<Can_Solicit_Customers></Can_Solicit_Customers>
<Can_Solicit_Job></Can_Solicit_Job>
<Can_Use_Job_Tracker></Can_Use_Job_Tracker>
<Can_Join_Career_Using_Gameplay_Interactions></Can_Join_Career_Using_Gameplay_Interactions>
<Has_Employer></Has_Employer>
<Can_Retire></Can_Retire>
<Has_Open_Hours></Has_Open_Hours>
<Overmax_Percent_Pay_Increase></Overmax_Percent_Pay_Increase>
<Highest_Level></Highest_Level>
<XP_Gain_Multiplier_Contribution_Max>0.3</XP_Gain_Multiplier_Contribution_Max>
<FullClassName></FullClassName>
<Speech_Balloon_Image></Speech_Balloon_Image>
<Headline_Icon></Headline_Icon>
<Work_Icon></Work_Icon>
<Wishes_Icon></Wishes_Icon>
<Description_Text></Description_Text>
<Offer_Text></Offer_Text>
<SocializationTopLevel_Text>SocializationCareerServices</SocializationTopLevel_Text>
<AssessNeeds_Text>SocializationAssessNeeds</AssessNeeds_Text>
<SolicitJob_Text>SocializationSolicitJob</SolicitJob_Text>
<Retirement_Text></Retirement_Text>
<Career_Responsibility_1></Career_Responsibility_1>
<Career_Responsibility_Short_1></Career_Responsibility_Short_1>
<Career_Responsibility_Icon_1></Career_Responsibility_Icon_1>
<Career_Responsibility_2></Career_Responsibility_2>
<Career_Responsibility_Short_2></Career_Responsibility_Short_2>
<Career_Responsibility_Icon_2></Career_Responsibility_Icon_2>
<Career_Responsibility_3></Career_Responsibility_3>
<Career_Responsibility_Short_3></Career_Responsibility_Short_3>
<Career_Responsibility_Icon_3></Career_Responsibility_Icon_3>
<Career_Responsibility_4></Career_Responsibility_4>
<Career_Responsibility_Short_4></Career_Responsibility_Short_4>
<Career_Responsibility_Icon_4></Career_Responsibility_Icon_4>
</ActiveCareers>
<ActiveCareers>
<SKU>EP4</SKU>
<ActiveCareer>Daycare</ActiveCareer>
<AgeFlags>112</AgeFlags>
<Can_Join_Career_Using_Gameplay_Interactions>x</Can_Join_Career_Using_Gameplay_Interactions>
<Can_Retire>x</Can_Retire>
<Overmax_Percent_Pay_Increase>0.05</Overmax_Percent_Pay_Increase>
<Highest_Level>5</Highest_Level>
<FullClassName>Sims3.Gameplay.ActiveCareer.ActiveCareers.Daycare,Sims3GameplaySystems</FullClassName>
<Speech_Balloon_Image>Career Daycare</Speech_Balloon_Image>
<Headline_Icon>ep4_ac_daycare</Headline_Icon>
<Work_Icon>hud_daycare_career</Work_Icon>
<Wishes_Icon>w_daycare_career_large</Wishes_Icon>
<Description_Text>DaycareCareerDescription</Description_Text>
<Offer_Text>DaycareCareerOfferTns</Offer_Text>
<Retirement_Text>DaycareCareerRetiredTns</Retirement_Text>
<Career_Responsibility_1>DaycareCareerResponsibility1</Career_Responsibility_1>
<Career_Responsibility_Short_1>DaycareCareerResponsibilityShort1</Career_Responsibility_Short_1>
<Career_Responsibility_Icon_1>w_daycare_career_large</Career_Responsibility_Icon_1>
<Career_Responsibility_2>DaycareCareerResponsibility2</Career_Responsibility_2>
<Career_Responsibility_Short_2>DaycareCareerResponsibilityShort2</Career_Responsibility_Short_2>
<Career_Responsibility_Icon_2>w_forgive_child</Career_Responsibility_Icon_2>
<Career_Responsibility_3>DaycareCareerResponsibility3</Career_Responsibility_3>
<Career_Responsibility_Short_3>DaycareCareerResponsibilityShort3</Career_Responsibility_Short_3>
<Career_Responsibility_Icon_3>w_handle_emergencies</Career_Responsibility_Icon_3>
</ActiveCareers>
<SkillContributions>
<Occupation></Occupation>
<Skill></Skill>
<Occupation_Level>-1</Occupation_Level>
<SkillGain_To_XP>0</SkillGain_To_XP>
<Skill_Level></Skill_Level>
<XP_Gain_Multiplier_Contribution>0</XP_Gain_Multiplier_Contribution>
</SkillContributions>
<CareerLevels>
<ActiveCareer></ActiveCareer>
<Level></Level>
<Title></Title>
<Stipend></Stipend>
<Task_Cash_Multiplier></Task_Cash_Multiplier>
<Job_XP_Low_End></Job_XP_Low_End>
<Job_XP_High_End></Job_XP_High_End>
<Daily_Perfect_Job_Bonus_XP></Daily_Perfect_Job_Bonus_XP>
<Goal_XP></Goal_XP>
<Required_In_Office></Required_In_Office>
<Days_To_Work></Days_To_Work>
<Wakeup_Time></Wakeup_Time>
<Start_Time></Start_Time>
<Day_Length></Day_Length>
<Downtown_Wakeup_Time></Downtown_Wakeup_Time>
<Downtown_Start_Time></Downtown_Start_Time>
<Downtown_Day_Length></Downtown_Day_Length>
<Reward></Reward>
<Reward_Text></Reward_Text>
<Description></Description>
<Job_Notification_Type></Job_Notification_Type>
<Uniform></Uniform>
</CareerLevels>
<CareerLevels>
<ActiveCareer>Daycare</ActiveCareer>
<Level>1</Level>
<Title>DaycareTitleLevel1</Title>
<Stipend>100</Stipend>
<Task_Cash_Multiplier>0.18</Task_Cash_Multiplier>
<Job_XP_Low_End>70</Job_XP_Low_End>
<Job_XP_High_End>200</Job_XP_High_End>
<Daily_Perfect_Job_Bonus_XP>25</Daily_Perfect_Job_Bonus_XP>
<Goal_XP>1250</Goal_XP>
<Required_In_Office>x</Required_In_Office>
<Days_To_Work>MTWRFS</Days_To_Work>
<Wakeup_Time>8</Wakeup_Time>
<Start_Time>9</Start_Time>
<Day_Length>10</Day_Length>
<Downtown_Wakeup_Time>8</Downtown_Wakeup_Time>
<Downtown_Start_Time>9</Downtown_Start_Time>
<Downtown_Day_Length>10</Downtown_Day_Length>
<Reward_Text>DaycareRewardLevel1</Reward_Text>
<Description>DaycareDescriptionLevel1</Description>
<Job_Notification_Type>None</Job_Notification_Type>
<Uniform>daycare01,EP4</Uniform>
</CareerLevels>
<CareerLevels>
<ActiveCareer>Daycare</ActiveCareer>
<Level>2</Level>
<Title>DaycareTitleLevel2</Title>
<Stipend>200</Stipend>
<Task_Cash_Multiplier>0.3</Task_Cash_Multiplier>
<Job_XP_Low_End>70</Job_XP_Low_End>
<Job_XP_High_End>200</Job_XP_High_End>
<Daily_Perfect_Job_Bonus_XP>25</Daily_Perfect_Job_Bonus_XP>
<Goal_XP>2900</Goal_XP>
<Required_In_Office>x</Required_In_Office>
<Days_To_Work>MTWRFS</Days_To_Work>
<Wakeup_Time>8</Wakeup_Time>
<Start_Time>9</Start_Time>
<Day_Length>10</Day_Length>
<Downtown_Wakeup_Time>8</Downtown_Wakeup_Time>
<Downtown_Start_Time>9</Downtown_Start_Time>
<Downtown_Day_Length>10</Downtown_Day_Length>
<Reward_Text>DaycareRewardLevel2</Reward_Text>
<Description>DaycareDescriptionLevel2</Description>
<Job_Notification_Type>None</Job_Notification_Type>
<Uniform>daycare02,EP4</Uniform>
</CareerLevels>
<CareerLevels>
<ActiveCareer>Daycare</ActiveCareer>
<Level>3</Level>
<Title>DaycareTitleLevel3</Title>
<Stipend>300</Stipend>
<Task_Cash_Multiplier>0.42</Task_Cash_Multiplier>
<Job_XP_Low_End>70</Job_XP_Low_End>
<Job_XP_High_End>200</Job_XP_High_End>
<Daily_Perfect_Job_Bonus_XP>25</Daily_Perfect_Job_Bonus_XP>
<Goal_XP>4500</Goal_XP>
<Required_In_Office>x</Required_In_Office>
<Days_To_Work>MTWRFS</Days_To_Work>
<Wakeup_Time>8</Wakeup_Time>
<Start_Time>9</Start_Time>
<Day_Length>10</Day_Length>
<Downtown_Wakeup_Time>8</Downtown_Wakeup_Time>
<Downtown_Start_Time>9</Downtown_Start_Time>
<Downtown_Day_Length>10</Downtown_Day_Length>
<Reward_Text>DaycareRewardLevel3</Reward_Text>
<Description>DaycareDescriptionLevel3</Description>
<Job_Notification_Type>None</Job_Notification_Type>
<Uniform>daycare03,EP4</Uniform>
</CareerLevels>
<CareerLevels>
<ActiveCareer>Daycare</ActiveCareer>
<Level>4</Level>
<Title>DaycareTitleLevel4</Title>
<Stipend>400</Stipend>
<Task_Cash_Multiplier>0.76</Task_Cash_Multiplier>
<Job_XP_Low_End>70</Job_XP_Low_End>
<Job_XP_High_End>200</Job_XP_High_End>
<Daily_Perfect_Job_Bonus_XP>25</Daily_Perfect_Job_Bonus_XP>
<Goal_XP>7000</Goal_XP>
<Required_In_Office>x</Required_In_Office>
<Days_To_Work>MTWRFS</Days_To_Work>
<Wakeup_Time>8</Wakeup_Time>
<Start_Time>9</Start_Time>
<Day_Length>10</Day_Length>
<Downtown_Wakeup_Time>8</Downtown_Wakeup_Time>
<Downtown_Start_Time>9</Downtown_Start_Time>
<Downtown_Day_Length>10</Downtown_Day_Length>
<Reward_Text>DaycareRewardLevel4</Reward_Text>
<Description>DaycareDescriptionLevel4</Description>
<Job_Notification_Type>None</Job_Notification_Type>
<Uniform>daycare04,EP4</Uniform>
</CareerLevels>
<CareerLevels>
<ActiveCareer>Daycare</ActiveCareer>
<Level>5</Level>
<Title>DaycareTitleLevel5</Title>
<Stipend>500</Stipend>
<Task_Cash_Multiplier>0.77</Task_Cash_Multiplier>
<Job_XP_Low_End>70</Job_XP_Low_End>
<Job_XP_High_End>200</Job_XP_High_End>
<Daily_Perfect_Job_Bonus_XP>25</Daily_Perfect_Job_Bonus_XP>
<Goal_XP>9500</Goal_XP>
<Required_In_Office>x</Required_In_Office>
<Days_To_Work>MTWRFS</Days_To_Work>
<Wakeup_Time>8</Wakeup_Time>
<Start_Time>9</Start_Time>
<Day_Length>10</Day_Length>
<Downtown_Wakeup_Time>8</Downtown_Wakeup_Time>
<Downtown_Start_Time>9</Downtown_Start_Time>
<Downtown_Day_Length>10</Downtown_Day_Length>
<Reward>Object:carVanDaycare/EP4</Reward>
<Reward_Text>DaycareRewardLevel5</Reward_Text>
<Description>DaycareDescriptionLevel5</Description>
<Job_Notification_Type>None</Job_Notification_Type>
<Uniform>daycare05,EP4</Uniform>
</CareerLevels>
<InappropriateActions>
<EventTypeId></EventTypeId>
<Priority>0</Priority>
<ScoldingTNS>CaughtDoingSomethingInappropriate</ScoldingTNS>
</InappropriateActions>
<InappropriateActions>
<EventTypeId>kBehavedInappropriatelyWhileOnTheJob</EventTypeId>
<Priority>-1</Priority>
</InappropriateActions>
<InappropriateActions>
<EventTypeId>kSimFellAsleep</EventTypeId>
<ScoldingTNS>CaughtSleeping</ScoldingTNS>
</InappropriateActions>
<InappropriateActions>
<EventTypeId>kAteMeal</EventTypeId>
<ScoldingTNS>CaughtEating</ScoldingTNS>
</InappropriateActions>
<InappropriateActions>
<EventTypeId>kEventTakeShower</EventTypeId>
<Priority>1</Priority>
<ScoldingTNS>CaughtShowering</ScoldingTNS>
</InappropriateActions>
<InappropriateActions>
<EventTypeId>kEventTakeBath</EventTypeId>
<ScoldingTNS>CaughtBathing</ScoldingTNS>
</InappropriateActions>
<InappropriateActions>
<EventTypeId>kSwimming</EventTypeId>
<ScoldingTNS>CaughtSwimming</ScoldingTNS>
</InappropriateActions>
<InappropriateActions>
<EventTypeId>kGamePlayed</EventTypeId>
<Priority>1</Priority>
<ScoldingTNS>CaughtPlayingGame</ScoldingTNS>
</InappropriateActions>
<InappropriateActions>
<EventTypeId>kWatchedTv</EventTypeId>
<ScoldingTNS>CaughtWatchingTV</ScoldingTNS>
</InappropriateActions>
<InappropriateActions>
<EventTypeId>kCookedMeal</EventTypeId>
<ScoldingTNS>CaughtCooking</ScoldingTNS>
</InappropriateActions>
<InappropriateActions>
<EventTypeId>kGrilled</EventTypeId>
<Priority>1</Priority>
<ScoldingTNS>CaughtGrilling</ScoldingTNS>
</InappropriateActions>
<InappropriateActions>
<EventTypeId>kWorkedOut</EventTypeId>
<ScoldingTNS>CaughtWorkingOut</ScoldingTNS>
</InappropriateActions>
<InappropriateActions>
<EventTypeId>kPerformedGuitar</EventTypeId>
</InappropriateActions>
<InappropriateActions>
<EventTypeId>kWentFishing</EventTypeId>
</InappropriateActions>
<InappropriateActions>
<EventTypeId>kPainted</EventTypeId>
</InappropriateActions>
</ActiveCareers>

Using that package in your game will break all of the other active careers, as all of their tuning is inside it. By removing them from the XML, you are overwriting the EA one with a version that only contains information for daycare.
Resources as you see them in S3PE overwrite anything with the same instance ID. Everything that you don't need to modify should simply be left as it was. Hope that clears it up

As noted, you should not delete everything else, you can edit only the parts you want.
And you need to check if another mod you have alters the same resource.

EDIT: Yes as CardinalSims said. All information for the other careers are missing now