Do you have RPM A-Arms yet? If you don't then you have waited way too long. I have RPM arms and aluminum adjustable piggyback shocks and my truck is almost invincible. I would defintely get the RPM arms, a Motor Saver air filter. If you want more power, you could go with an OS 21 tm engine, but you would have to beef up the drivetrain first to handle the power. If I were you, I would get all the suspension dialed in first, because power will not do any good unless you can transfer it to the ground. After you get the suspension tuned and the drivetrain beefed up, then you can add power without breaking too much stuff.
I'm still new and these are just general ideas, I'm sure the veterans will chime in with more detailed stuff.