brackish doesnt have much choice when compared to fresh or salt water. the fish available generally get big (mono's, columbian cats, scats, archers, dats), or have a predatory nature,(snowflake moray 'G. tile', puffers, 'freshwater' lionfish/stonefish). added with the huge range brackish has (from 1.001sg to 1.021sg), can make choosing fish a pain in the arse. so you gotta do your homework, or you could lose fish.
things like figure 8's and green spotted puffer's would go well, but f 8's need low end brackish, and GSP's need high end brackish/marine as adults. but obviously arent community fish. the same applies to monos and scats. they need marine conditions as adults.
for a community tank ,bumble bee gobies would be fine, but might get lost in there due to their small size, some other goby species would do well, but avoid dragon gobies. they get to 12"+.
chromides would be fine, as would mollies and guppies. stay clear of archers mono's and scats though. they get too big, and prefer to be in shoals of 6+. with mono's any less and they'll kill each other as they can be aggressive.