"O"riginal "P"oster.

Your airplane has a very unusual configuration with it's symmetrical main wing and cambered tail. As configured your plane is not meant to be seriously aerobatic, but gentle and slow. Unless you change the tail to one with a symmetrical airfoil, you will not be able to rid it of it's current tendencies, though you might be able to reduce them in accordance with pimmnzs' suggestion.

Airplanes with tails like your airplane's sometimes have the characteristic of nosing down at higher speeds, which I would expect your airplane to do, since the camber alone will cause the tail to rise with higher speed and the symmetrical main wing's lift increase depends only on it's incidence, not it's camber. It's even possible, again depending on configuration, that if flown at a sufficiently high speed, the nose would "tuck" and not recover no matter how much up elevator was applied.

The term elliptical is usually applied to the wing planform (shape as seen from the top or bottom) or it's lift distribution, not the airfoil.