I have this idea:

Would it be possible, to take a guitar pro song, then export each track seperately into a midi file. Then, I would take each midi file, and put it into a recording program and put sounds on it that are better than RSE (VST if i'm right?). Would this work?
Yes, i do that with my drum tracks and then add guitar on reaper
You can have good vsts if you take the time to look. I have great strings, bass and there are many drums machine such as Ezdrummer, Addictive drums, etc. Except for the guitar. There are some but they sound like crap. There's Prominy LPC but you have to get an amp simulator like guitar rig 3. But the best way to have a thick distorted sound is still a good old guitar plugged in any cheap interface.