Instead of spending on pickups, why not try "rethinking" your EQ?
The styles of music you describe tend to have a tendency to use the mid "scoop" style EQ, loads of bass, no mids, and loads of treble (which without the mids, tends to get lost, especially when combined with downtuned guitars using the same EQ).
Your issue is more that the guitars are EQ'd in a similar fashion, and you're all "competing" for sonic space. The addition of distortion and/or fuzz will also be robbing you of bottom end clout.
Try having a mid-heavy EQ, as this will enable your sound to cut through the wall of guitars. Try using less gain and more volume on your amp, and also turn the distortion / fuzz control down. If your distortion / fuzz pedal has a "mix" control, enabling you to mix your "wet" & "dry" signals, turn it so that you get more "dry" signal through.
What will be more effective in the mix is a mildly overdriven sound, rather than a full on distortion.