I have the Crawler/IT's in am MXG custom swampashstrat (Patrick Eggle made those) and the hb is quite beefy, warm, growling and has enough bite for me. It can do a lot of styles, also hardrock, nevertheless has some roundness/sweetness to it. I like it, but it's not everybody's cup of tea.
But, I have the VHII/MM's in an Fender American Series ashstrat. The VHII is really the dog bollocks with a bit of gain. Bite, yeah, but not brittle and annoying, enough meat on the higner notes, very clear and balanced pu. When you dig in it screams and overtones jump out, roll the volume down is surprises with a sort of singlecoilvibe to the notes. Great rockpickup. Could be the one for you.
There are more options: Abraxas, beefy PAF-ish-tones, say a really hot Mule. And the Holy Diver, which will def. beef up your strat, bec it has quite some mids. It's has a bit more modern hardrock/metal tone to it, and at the same enough pedigree to do classic rock and fat blues(rock).
Personally I think the Abraxas would cover a lot of your styles. It has a bit more chime, air, bite and PAF-character then the hotter, more compressed Crawler. It will provide the necessary beef to a strat.