RE: Won't roll!
I second what R/C Ken and John said. On that type of aircraft that you have- if you increase the throw rate on your ailerons, it won't improve your roll rate . Matter in fact you could make your plane more unstable in the roll. The Hanger 9 Fokker DVII has a very terrible roll rate. I tried playing around with the throws and it got more unstable when I tried to do a roll at a higher non-recommended control throw. Like John said, it's the designed of the dihedral, and shape of the wing that contributes how it will effect the aircraft in a roll.
If you study the side view of a trainer wing and compare it to a Extra or Edge wing you can see the difference in dihedral among other things. Your plane is a powered glider designed for introduction- nice casual flying on a good day for training pilots, not for stunt flying other than loops.
Pete