I'm aware Cross is still canon, yes, but we haven't had several loose ends with the Trigger cast tied up yet, namely what happened to Crono and Marle.
As for an entirely new setting, that's mainly what Kato set out to achieve with Cross, bringing new characters and stories into the fold.
So, my question is this: Which would you rather see next? A new Chrono game or a game that wraps up Trigger once and for all?