I'd like to see a Time Mage myself. That being said, any time a new job references previous entries in the series, there's a player expectation that it be faithful to all the previous iterations. You see this in jobs like DRK where we still see complaints about the job not using HP as a resource even still, seven years out. I think this is why more of the newer jobs have been completely fresh, to allow them more room to design into.
You could very easily create a 'not-a-time-mage' job with an oddly familiar conical hat, that uses Void magic to manipulate space-time and apply DoTs, without having it be beholden to any previous expectations around Time Mages. A recurring boss in Eden uses some neat 'void magic' spells, so there's plenty of inspiration to draw from (if they don't end up in the BLU spellbook).
You could design Haste as a personal cooldown or even a trait. Perhaps 'Slow' could be used to delay a spell effect and make it pop up later under buffs, like a 'delayed' spell. Perhaps 'Float' could let you cast while moving. Warp could let you set up an interactable teleporter between two points and a set number of charges. What if X-zone worked in reverse, bringing in an eldritch horror from the void briefly to psychologically damage the target? There's a ton of creative approaches that they can take to time magic, the only limitation is going to be how players respond with their preconceptions on how a 'Time Mage' is 'supposed' to play. Which is why I think they're better off creating a job that pays homage to them without fully committing to being one.
