How about skins for our favorite crusaders, with no particular benefits, that you can buy with rubies and its to make them look different/cooler and also to "change" them. so lets say if they're human, there would be a skin to make them like a robot or something, so they are no longer tagged as human, but a robot or whatever.

Agreed, cosmentics don't matter but changing a tag is a great idea!

Skins are themselves a fine idea, but I think allowing us to change a character's species and/or gender is a very bad idea. For example, Emo is a very strong DPS, but has the drawback of losing his DPS if he's next to a human. What these skins would do is functionally remove Emo's drawback, severely damaging the balance of the game. Completely non-functional skins, that did nothing but change the appearance of the game, are totally fine, but if they were to cost rubies, the we should be able to purchase rubies with real money, since the main point of skins is to encourage players to spend said real money.

I thought this idea would give us even more options to mess around with and if they do decide to add more crusaders with unique buffs based on the type of crusaders are next to them, we can switch around a whole bunch of crusaders. Of course this would prove to be really OP if you can do any crusader as long as you have a skin for them, thats why i feel like the skins should be limited to some degree of crusaders, so that you don't have 2 or more crusaders with unique buffs stacked