I have absolutely no knowledge of modding outside of sound mods, and the installation of mods. Keep that in mind, in case I say something stupid. Also, as a British user, I will use "colour" as opposed to "color", sorry.
So, today I went to a gaming cafe with my friends and played some Sm4sh, which was fun. My friend took the player 1 slot, and I suddenly realised how odd it feels to play in a different colour. I've played this game for 3 years and only now have I been anything but player 1. So, I started thinking, "is it possible to change all the player colours to anything? Surely it's just a matter of recolouring a few images." Now I do realise there's A LOT of player-coloured things, but would just making them all a tad fresher with some new looks be impossible, difficult, or easy? Furthermore, would it just be from one solid colour to another, or is there potential to use patterns for the images?
Maybe, somehow, nobody has considered this? I've looked around and nobody seems to be trying to alter these things.
I've been looking into this for quite a while as well. As a previous poster said, it's more of a matter of that the color files themselves are hidden deep in the game. If anyone can find them, it is not hard to change at all.