Good tips...

to add my t'penworth...

The idea of using the filter to get a good bass sound by whacking up the resonance at the low end is quite a cool one. I do that occasionally doubling up the bassline, one with a hi pass filter and one with a lo pass filter, at one of the magic frequenicies (often done by ear though). Leaned this form DJ Glowbones, who learnt it form Sol Ray.

But... what is important is to tame this with compression and that it's an effect, not part of the EQ process.