Hi,
you could try to replace the quilt in the Page Initialization, adding something like this (untested):
<#if page.name == "ViewProfilePage">
<#if page.context.user.id == user.id>
${http.response.replaceQuilt("ViewProfilePage","ViewProfilePage.User")}
</#if>
</#if>
and creating a custom page ViewProfilePage.User with the different layout...
i think the simplest way is to contextualize your "private" component with a if condition
for custom components just put
<#if page.context.user.id == user.id > .. my custom components ... </#if>
For standard component you will have to create a custom one one to ovverride it :
--> name it : standard-component-id@override
--> add your conditionr before
<#if page.context.user.id == user.id > <@delegate /> <#-- this call the standard component --> </#if>
