Also, somebody had it backwards, the top wing should have positive incidence compared to the bottom because you DO want the top wing to stall first on a possitive stagared wing Bip. but 0-0 would also work

you could also try some aileron differential, more up than down

4 degrees right thrust sounds like a ton to me

what are your throws for your rudder elevator and ailerons?

does it taxi straight?

could be nose heavy also if the rudder and elevator is ineffective
you got alot of 2 cents to go with here
good lookin model, dont give up!