Actually there's not much to do; besides a couple of strip clubs with 4~7 rated chicas, the old and rusty Anthonys, a walk for 5 blocks in the 1st/Ruiz/Costero street full of curios shops and locals, the rancid Papas & Beer and... nothing else. But, if you like walking for 15 minutes looking cracked boats in the ocean, then try the marina (they call it Malecon); but ask the girl first, maybe she will be bored as hell while you think is a romantic walk.
Local chicas are open (or curious) when a gringo approach them. It could be a nice adventure trying to date a local girl; but anyway it will depend if you find a good one.