I'm not usually one for wanting to remake a game with better graphics, and I think adjusting or updating the gameplay of a game is very contentious.
But personally, I'd love to see a Chrono Cross remake. It is a very good game, and I'm not sure in what capacity I'd want a remake to take. But I think returning to an Akira Toriyama art style, to maintain consistency with Chrono Trigger, would definitely be a good idea.
I do think square handles his art style with a lighter touch, these days. Characters and environments are rounder and appear quite buoyant. I'd like to see something a little sharper for Cross.