If the music is something simple along the lines of early Everclear, Nirvana, Mudhoney, leaning towards a more punk than rock sound, how could a bassist really stand outand fill the space that a rhythm guitarist would? Gear is a cheap Peavey 4-string, Ampeg 4x10 and Portaflex. It's not a great setup, but those three pieces of equipment are unlikely to change. He could be coerced to add fuzzes, overdrives, etc. What about playing could bring out the bass more? He's not an adept bassist, but this music is extremely simple, sometimes only some fast power chords on guitar he follows along with. What sort of overdrives really sound great and have a guitar-like presence without getting too farty? I've been looking over some combinations of blending clean signal with Big Muf style fuzzes, kind of liking that sound personally but I'm not a bassist and have no idea how something will sound in band context.