I suppose only room mic would be alright, but they must sub mix live to mono which is very cool if you can commit. really, only four mics are necessary for drums, IMO; kick, snare, overhead L, overhead R.
micing hihat sucks ass, top snare is where all the punch is and thundering toms are cool, but absolutely not important... plus they f-up the two buss.
I love panning close-miced gtr cabs with distance ldcs and room mics to get depth and image, but mono gtrs can be great.
bass and main vox are always mono, and backup vox can be sub grouped live.
again, the songs need to be final draft/written or the band needs to be able to flesh things out on the fly... but yeah, eight is enough. you would not attract the next nickelback or top shelf a&r though.
