The Caitian first appeared on Star Trek: The Animated Series, but have also made minor appearances in several Star Trek movies. The feline style beings vary from version to version, but we do know that they are members of the Federation.
A Caitian character in the new series might give us a chance to explore their habits and culture a bit more. Perhaps the Caitans can’t eat replicated food and need real meat? This would be the kind of interesting quirk that could cause problems, like the Cardassians loving heat due to their reptilian ancestry.
Next: The Q