I'd love more original creatures, in the same league as the superb Dream Lord (masterfully played by Toby Jones, of course). Give the Angels, the Cybermen, the Daleks (after the 50th, of course) a rest for a while.
River's had her run (heh), I feel. She and the Eleventh should bow out at the same time.
Capaldi should make for a darker Doctor, I hope. More moody than happy chappies Tennant and Smith. Moody and gruff like Ecclescake.
Yeah, dat would be suh-weet, bruv. Innit. And ting.