You probably want to post here, actually: http://www.talkbass.com/forum/f8/
For me, I love my ErnieBall MusicMan basses, and I like buying them from ThePerfectBass (the sponsor of this subforum).
A lot of what you're doing is going to be technique heavy too. Playing a pick does bring more mids out front, especially if you pick right over a pickup. If you need deep, fat, round and blooming lows, thumb or finger picking IMO will be your best bet (or EQ'ing in somewhere around 150Hz). Pick playing for that aggressive tone, and slap for the well, slap tone.