your too tail heavy !!!
if,, you are really .5 pos
you have to remember tail weight will make the airplane sensitive .but not responsive and viseversa
move the nose weight forward untill the feel is right more nose weight better elevator feel as always you can go too far both ways But tail heavy can trick you into thinking your nose heavy.
even with .5 pos in the wings when you roll it inverted you should hardly need any elevator input
in fact my airplane rolled to inverted with rudder has a down elevater application requirment delay time of a second
with the c/g right the elevator takes very little movement to make a changeit is much more responsive
make sure the .5 pos is relative to the design thrust line not the engine thrust
and trust this advise
this comes for years of design and development
Bryan