Re: which banshee mod?
1st thing to do is install pipes\silencers and get a kn filter with outerwear, leaving the stock lid off the box. Unless you go through water of course. Rejet.
All the other mods will be excellent at moving more air, but should be done after or the same time as the pipes and filter.
Careful on pipe selection, they can make or break your torque curve.
Porting will make a very awesome difference!
If you do port the cylinders, its a good time to do a small overbore(.020") for some more power as well.
I originally had pipes and filter only, and it was cool. Then at the same time, i ported the cylinders, did .020" pistons, milled the head, and it was a new animal!
Dont waste your time with the boost bottle. I tried one, and i felt i lost some power.