So I did this, more for my own use than anyone elses, but you may use it if you wish.
Backup your original files before installing.
If this breaks your game and ruins your life it's not my fault, and by reading this you have agreed that.
The file contains the "mlm_team_back.igb" file, to go in whereveveryouinstalledmua/ui/menus.
It also contains an edited "team_back.xmlb", also to go in ui/menus.
What it is:
a team select screen with 50 character slots (in the pic above only 33 are in use, but the others are in there and work).
It's got an extra 3rd riser tier at the back, allowing a 3rd row of characters.
The order of the pads is completely different, it now goes in order, from:
Hawkeye (pad01) >>>>>>>>>to Wasp (pad18) left to right (1-18),
then up and back to Vision (pad19) <<<<<<<<and now right to left to Squirrel Girl (pad47),
then up and back to Hercules (pad48) and >>>>>>>>>>right to Dr. Strange (pad60).
Going left from Hawkeye(pad1) loops round to Strange (pad60), and going right from Strange goes to Hawkeye)
For everyone else if you press left it goes to the character to the left, right goes to the right (unless there is no character there, in which case keep pressing left or right till you come to someone).
There are no pads numbered 30-39, because thats the numbering convention in this game.
You will probably want to put your larger, or flying characters in the back tier (pads 48-60) so they dont obscure everyone else, as I've done with Hulk, thing, Strange Torch etc..
I've remove the Human Torch and Ghost Rider flames because I wanted to.
I've boosted the lights so you can see everyone, even those at the back, and moved a camera back so the camera can spin to see everyone as you scoll through.
You will need to edit your herostat to put characters in the appropriate places.
That's it. If you like it, use it, if not don't.