Each guitar has it's own intrinsic tones. The choice of pickups will modify that a bit. But the major factor in your overall sound is how much distortion you use, and what kind of distortion it is. And all of that comes from your choice of amps and pedals.

If you play with clean, undistorted tone, then your choice of guitar/pickups becomes very important to the final sound. As you add more distortion and effects, they take over the final result, to the point that almost any axe will do.

So, if you want to play sweet, clean stuff, choose accordingly. You can use that same axe for heavy stuff just by adding gain and effects. You may end up with 1 guitar, and 6 amps.

From what I've been hearing from Dr_simon, you could just get a Line 6 Variax, and a Spider II, and spend your time experimenting with switch patches instead of shopping for gear. I find that concept distasteful on a spiritual level, but I will admit it would free you to concentrate on composition instead of tone-quest. YMMV.