I think it's more than small doses, he's been known to do all that for fun for Gladbach and Switzerland and to a fairly high degree. He hasn't quite been given the opportunity here yet but I think that's more to do with him acclimatising himself to the league and obviously playing here is a different prospect.
To be a controller of the midfield the need for pace is overblown, Pirlo, Xavi, Alonso, Modric , Kroos, Santi, Scholes et al are not known for their pace. Of course these guys were/are at the apex of world football but the point remains.
I'm not lumping Xhaka with them as he has a long way to go but he's still quite young and can still vastly improve, I agree with him not being an ideal b2b player though I said something similar. A pivot of Xhaka and Jack might have potential, Xhaka/Coq would be fine also. I'm not sure about Santi because he needs someone more mobile which perhaps why don't seem to played together often.
If Santi is out though Xhaka must play as we lose all semblance of control without him, Elneny is at most 'neat and tidy'. Xhaka is the only one who can hope to replicate what Santi brings to an extent.