I understand what you mean about costumes (although, my general view on them is that they are just colourful, sexy and fun with some really bad exceptions), but, in reality, I doubt that the costumes (floor or ice dancing) for latin dances are actually any cheaper than the costumes for any other style of (ice) dance.
And "hand waving"? It seems that you are mixing up latin dances with something else (like dramatic Russian style FDs on ice), as latin dances usually don't require any hand waving - neither on floor or on ice.
Unfortunately, P/C can't do just rhumba. Another latin rhythm is required outside of the pattern.
