Gambit

I'm a little surprised how there's a push for this. Gambit was never more than an ancillary character in the comics, he only became more popular thanks to the 90s cartoon show.

Hell, his whole schtick was that everytime they ran into a villain he'd look at Gambit and say "Huh, what are YOU doing here?" and we'd find out Gambit had a connection to them in some contrived way.

It got to the point you'd wonder if Thanos would show up and it turns out he and Gambit went to High School together.