Here's what you should start out with, I have all these mods on mine and it hauls ass with stock crank and stock cylinders
Vforce 4 reeds
K&n dual pods
Toomey T5 pipes and silencers
+4 advance timing
15/40 gearing
The 15/40 gearing is really nice for trails, you can stay in 3rd gear all day long and still have lots of power for technical shit.
Start with those and see how you like it. There's a new site sponsor on here Young Guns Racing that's selling some quality pipes for around $350 I think, shoot him a pm and see what you think.