Hello,
We had a similar need, Unfortunately OOTB tabs are not controllable, What I did was, I removed the Out of the Box Pages in actionmodels.xml file and created new pages in the Layout , that gives you the flexibility to rearrange your summary page and structure the tabs based on the most relevant information, I have two tabs "ECN Summary" and "Workflow and Lifecycle"

You can hide any of the below tabs as needed in ChangeManagement-actionModels.xml , I recommend update to be done in custom-actionsModels.xml
<model name="changeNoticeInfoPageTabSet" >
<submodel name="changeNoticeDetailsTab"/>
<submodel name="implementationPlanTab"/>
<submodel name="simplifiedImplementationPlanTab"/>
<submodel name="changeNoticeProcessTab"/>
<submodel name="changeObjectsHistoryTab"/>
<action name="sysnavTab" type="sysnav"/>
</model>