Fellaini will always have a role to play against the more physical and taller sides. I won't be surprised to see him against stoke.
With Smalling back in the team the need for Fellaini in the side isn´t really there anymore. When we had Bailly and Blind at centre-back he was a good choice, because Blind is a midget and Bailly has been quite average in the air so far. But with Smalling back we have that aerial presence in the defence and offense (at set-pieces) that we lacked with the other two centre-backs.