Custom Wizard definitely has a broad range of use/capabilities.
However to limit who can edit a wiki. Use Groups and category permissions.
So for example Bob seems to be very knowledgeable and has asked if he can help/submit & assist maintaining the database(s).
He applies to join Tree Wiki Group.
Tree Wiki Category security settings
- Everyone - See
- Tree Wiki Group - See/Create/Reply
You can also set a Setting that when someone tries to post in a wiki group topic it displays
“You must be a part of x group. Would you like to apply?”
This can be configured to be a link to take the person to pm group owners.
From here I will leave this for someone with better knowledge to answer your other queries.