Don't get me wrong here, but I did think about it, and at the end of the day, it just wouldn't seem right to add Thomas to the roster. Same with characters such as Nemo, even with a bit of work, it still wouldn't feel right to have Thomas fighting. He's a train, and it just doesn't make any sense to have him fighting. The CARS characters on the roster are already crossing the line now, and Sir Topham Hatt works well as a fighter, for he has access to railway tools, and my plan was for Thomas to be a part of the engines to be summoned for Hatt's Grand Finale move!
I still think Thomas could work. Considering the fact BWBA has probably made Thomas more cartoony than ever, I think Thomas could have some merit as a fighter. For one, I think it would funny for Thomas' up special if he could be picked up by Harold the Helicopter! That or use OpThomas Prime from James Farr's TrainsFormers parody series.