To be honest man the key is to not over-process your raw files.
When I do just literally the bare essentials to a guitar tone, high pass, low pass, and an obligatory wide 2-3db cut at 900hz if revalver is involved, a surgical cut at 100hz to kill rumble, and maybe one or two other minor cuts or boosts, I always get a much better sounding tone. More natural, bigger, wider, heavier, which is everything I'm usually going for in the first place.
I *ALWAYS* overprocess my guitar raws, and then as I carry on refining the mix, or do another iteration of the mix, I always cut down on the processing of the guitars especially. Just try and keep them as raw as possible and you'll probably get what you want as long as you dialled in a good tone to begin with.
Also try setting your high pass and low pass, THEN dial in your tone. I find that I end up dialling in huge amounts of bass for a thick tone, then I high pass, low pass, 10khz shelf boost, 100hz surgical cut and then turn off my eq and realise my tone is boomy and fizzy as fuck. I seem to subconsciouslly compensate for the basic eq'ing that I do, because I find that when I high pass and low pass I most of the boom and fizz that I didn't like in the raw tone, and I'm just left with the good stuff, so don't be afraid to experiment with what look like ridiculous tones. Jason Suecof puts his bass at 10 on 6505's I believe.