I would guess 140mm for the balance point to be a bit aft for a 40 size plane. Sometimes the mfg gets confused and states a balance point for a larger version of the same model. Your aileron throws don't appear excessive, still, toning them down may be a part of the solution. It looks like you are on the right track. Good luck.

edit: I just checked the Tower site and got some CG comparables for other Phoenix 40 size models.

Extra - 90mm
Yak 54 - 105mm
Sukhoi- 110mm