Dark blue on black never looks good IMO. Well, unless you're Black Canary. And a cartoon.
Actually, if he'd swap the black pants for something in dark grey, it could work a lot better. Regardless, every Doctor has had alternate looks during their tenure, so I'm sure Capaldi will follow suit.
Thing is, that red lining is awesome, but I think he's going a bridge too far to show it off. I mean, he has to deliberately flip that thing open with the top button fastened. Why pretend to be a magician if you look like you're making an effort to show off your tricks?