I'd say go for a caribe shoal, more color and more entertaining as compare to others in the list and cheaper too.
geryi is rare and nice to have but they are too expensive, if one get eaten then you are down $$$$, if you have the cash and really want them, go for geryi. but if you ever want to sell them it'll be difficult since not everyone has that much cash for fish and if you sell cheap you won't be getting your investment back.
other serra is just wasting the space in 180g and less you have a very active large rhom.
aimara will out grow the 180g and doesn't sound like you can get any larger tank down the basement so you either build a large plywood one or a large pond.