[@Isaac]

I didn’t say changing timelines, I said time altering as in altering an aspect of time. Yes, touch would be at least one drawback but for how long can they forward or rewind the one person or object? And you say that you couldn’t do it to a building so, what kind of objects? How big or small? 

All and all, the biggest reason it’s a no for me as a GM, is that I have to consider how enjoyable it will be to work with a character like that. Most people I doubt would love to re-write a whole scene or guess which point they would need to go back to. Heck, as one of the GMs who has to eventually write for the villains going against our heroes, I sure don’t want to have to re-write different points or play the backwards game.