I wouldn't mind the revenants being the defaults for some characters IF they were actually uniquely different playable personalities of the character, i.e. the revenant character spoke like a revenant with their own evil intro dialogues. After all, MKX had this if you chose a revenant skin.
Instead they have the same heroic intro quips they always do, which basically demonstrates to me that the human version of the character is the default and correct form for them that their character has been built around, whilst the revenant skin is nothing but a meaningless cosmetic no different than dressing them up as a Batman villain, a witch or a KGB officer. In which case, I want to the characters to look human on the select screen if the game is going to be constantly demonstrating to me they're normal and human whenever they're played with.