RE: Whats better than an avistar?
Sounds like you have some experience with the high wing trainers. I'd go for a low wing trainer like the Goldberg Tiger 2. 40 size.
I have one (look at my avatar) and it has an OS .46 AX in it. Flies great!!! And, it'll handle some wind unlike high winged planes.
The Tiger 2 runs about $140 or so...has trike gear but you can make it into a taildragger.
dave...