Coffee shop - Sacer!!! she works there and loves it
Beach - good question... Solace-3 does not have real beaches, only small artificial indoor ones.. I guess if we count those then Willow. If we don't then Oniria, who's home planet is largely made of oceans and small islands!
Nightclub - Willow and Vice in equal measure. Though I've been toying with the idea of Seth's main informant living above and working at a brothel/nightclub, so it may be that he too could be spotted there commonly.