I'll give a few suggestions that I consider more necessary in Q2A. If you believe that you can develop some plugins would be very interesting.
- turn off downvotes
- User block user
- see favorite users in the user profile.
- receive private messages only from favorite users
(It would be very interesting to Q2A have these social, followers, block, etc.)
- top 10 best users of the category (more best answers)
- Easier migration of a Q2A site to a new server.
I'm sure these improvements would please a lot in Q2A.
Thanks. I have many other suggestions if you want. :)