Dark and loose sounding guitars can be some of the trickiest to deal with. I have to second the EMG 81 as well. Personally, I haven't been into them in years, but it should definitely tighten up the response and feel and give you more cut. I'd also look into the EMG 57. I can't speaker from personal experience on those, but a friend of mine slapped one in a muddy sounding flying V of his and he says it kills now.
If you're against the active route, I'd recommend the WCR Icebucker. It's not overly hot, but it has more push than you'd expect and has a nice tight, percussive feel with good cut. I absolutely love these mated in the right guitar. I have a set I've tried in 3 different guitars, one of which is a V that has a looser, bloomier character and it was great in there. I'm always a little hesitant going with hot passives in dark & loose guitars. I'm not saying it can't work, but in my experience I've found that with rare exception going with overly hot passives in a dark & loose guitar just resulted in a muddier sound.
If you're against the active route, I'd recommend the WCR Icebucker. It's not overly hot, but it has more push than you'd expect and has a nice tight, percussive feel with good cut. I absolutely love these mated in the right guitar. I have a set I've tried in 3 different guitars, one of which is a V that has a looser, bloomier character and it was great in there. I'm always a little hesitant going with hot passives in dark & loose guitars. I'm not saying it can't work, but in my experience I've found that with rare exception going with overly hot passives in a dark & loose guitar just resulted in a muddier sound.
Forgot all about them but might have to put them back on the radar.