http://www.mediafire.com/?21jjen4ynfi (no vocals or piano intro :p)

This is my first attempt at recording guitars, programming drums and bass, and putting it all together. I used Guitar Rig 3 for the guitars, DFH for the drums, and Trilogy for the bass (pretty meh sounding if you ask me, although I probably just don't know how to properly use it lol).

I mixed everything with Reaper, and my "mastering" consisted of some hard limiting in Audition.

Tell me what you think and how I can improve it. I have a feeling it might be too bassy but I'm monitoring with Sony MDR-V600 Studio Monitor headphones so I'm not expecting the best results until I get better monitors.

Not bad man. The rhythm guitars need a bit of tweaking. They sound very washed out. Not bad, just a bit hollow really.
Could have been so much worse, so I think you did quite well.