It totally depends on where I'll be wearing it, what I plan on doing and who is going to be around:
For active stuff around a beach I'll wear a thong bottom (I have a bunch of separates) and a rashguard, and usually bring along a pair of shorts to pull on to cover up if I'm going somewhere where a thong is inappropriate.
For swimming at a public pool I wear a one-piece and a swim cap (both are regulation).
Regular vacationey or cottagey stuff is when I usually wear a typical two-piece "bikini", and again the amount of coverage totally depends on who I'm with, if there are kids, relatives or any super prudish people around
I don't like really patterned stuff so most of what I have is in black, navy, nude or some solid color. Fit, how flattering it looks on me, and quality are really the only factors I care about, I don't care at all about brands other than quality and making note of what size of
X brand fits me so I can order them online without trying them on