Stick with an Avistar until you develop the technique. Don't move on until you've landed her 20 times or so without needing to repair balsa or straighten landing gear.

Well, since you've flown an Avistar but don't want one I'll assume you want something more advanced. Also, you don't say whether you want an ARF or a kit, so I'll assume ARF.

A Big Stik is a fine "advanced trainer" that is more advanced than trainer, but very predictable. However, it flies where you tell it and will not help you regain control passively like a trainer will.

The Great Planes Easy Sport 40 is another good step from an Avistar.

I like my Kangke Super Kraft SK-50, but it might be too much unless you have an instructor or at least an experienced spotter to trim it out and get you started. It's a nice flier, but has a huge vertical stab with tail wheel and tends to weathervane on the ground if you're not careful.

Any plane you choose should have a good checking over and the first flight by an experienced flier. Reverse the ailerons or miss the recommended C.G. and your maiden flight is short and painful.