Really not my field (don’t have such case), but if I’m not mistaking you can create a group per user (may be even a category).
From here can’t you have per page permission ?
There is also a feature to have a userpage in Tiki (Admin => Wiki => User's information page)
Personal Wiki Page: UserPageBsfez
A direction too ?
But this is a full and complex case and it’s going to be hard to help you using the forum.
You should break issues down to small pieces... or try a Tiki consultant to guide you all the way.