I'm sticking with Marie Rose. I've hyper-focused on playing and learning her stuff that I've pretty much lost the ability to play any of the other characters I've tried, including Kokoro. Much like the recommendation to play Devil Jin over Jin back in Tekken 5, I don't think many of the players get that I would have enormous trouble playing a more complex character.
That said, I do like playing Bayman, and I can still sorta play him well enough. So I'll give him a shot for a bit.