I've got a les paul that I play as my standard git, but I've also got an old beater ibanez GIO that I don't know what to do with. I realize it's not a great guitar, but I LOVE the idea of customizing it just as a hobby. Even if it turns out terrible, I would have a lot of fun just working on it. I was thinking about customizing it to get a unique sound out of it that I can't get out of my gibson. I mostly play heavy rock, but I wouldn't mind something that could get a heavier sound than my gibson. Any suggestions for upgrading it (new pups, etc.)?
easy things to uprade that would be beneficial to the guitar:
tuners, bridge, nut, pickups.
if you want a more metal sound, could always install some active pickups and an active eq system.

id say if you did all that, you'd get a bit of experience in changing the hardware, and rewiring the guitar. you may even have to route a pocket for a battery box for the active pups if youre up to the challenge. and if you do some digging, you could probably find some interesting wiring to hook up.