I've been struggling with setting similar features across a number of blogs on a multisite, and from recent posts I see others have similar issues.
A few tools which sound like they might help:
Site Creation Wizard
YD site wide options
New Blog Defaults
I've been using new blog defaults, which seems great,
I have tried New site wizard and site template but both these are limited to creating new sites, not modifying old ones.
When I tried both these plugins they did what they said, but when I tried to post from the new blogs, I couldn't!
Any suggestions (and hope the list above is helpful to someone)