Both, but the night should be advertised properly with regards to the music policy....very few, if any nights can play 100% newies/underplayed, so IMHO the best thing is to have a mix & to have resident DJ's & guests who are proper DJ's & can keep a floor busy without totally selling out, throwing in a few left field plays, as/if the night becomes established this can then be gradually teaked....as Barry says, start small & build it up, if neccessary a bigger venue can be used if & when required.....softly, softly killy monkey.....get the punters onside & then gradually take em on a journey which is your vision for the clubs music policy.....as Patto says the structure of the sets is everything....I would rather be in an intimate club that is full with atmosphere & a full dance floor, than a big club that is half empty, with no atmosphere....
Russ