I am a new pilot and bought my Airhogs Ace jet just a couple weeks ago.. first time out, it took me a while to get hang of it, but noticed it wanted to go nose up big time until I left off the throttle some... so, I added a small metal screw near the cockpit (see first picture) to give it a little more weight on the front to help balance out the COG... it still does want to climb a little on my take off throws, but not near as bad and I can keep it up in the air for a good while, do circles, etc..

But was curious if I could do additional mods to help out?