Are some people really that upset by this? If you're going to give characters alternate customs, something like this was always going to be the most obvious choice for Zero Suit Samus. The only other alternate custom choices for Zero Suit Samus are her outfits from the original Metriod which are even skimpier, or her military outfit from the Other M flashback cutscenes, which last I checked, just reminding some Metriod fans of Other M's cutscenes causes them to have a mental breakdown.
Seriously, the big news here is we got another character with a real alternate custom, which just keeps increasing the chances more will as well. Unlike Brawl were Sakurai outright said Wario is the only character who would get one, we've already gotten several and Sakurai has never once said these are the only exceptions this time.