I think we'll see a lot more of him if we sign Sanchez in January. Having Sanchez would allow us to play with a symmetrical(ish) pair of wingers in either Silva/Sanchez or Sane/Sterling. (Weird coincidence how all their names start with an S)
Silva's not going to be playing too centrally a la David anytime soon, not unless it's as a false 9 which I don't think is a strong position at the moment (Guardiola normally puts Sterling there after a few minutes of trying Silva there). So it's only going to be the right. I don't think either Sterling or even Jesus for that matter really fit Pep's requirements for a left sided winger.
So as it stands we're always a bit lop-sided with Bernardo in the side. Not so much of a problem when it's from the bench but as a starter the asymmetry can cause a tactical headache.
He could revert to the side that beat Feyenoord. A 4-4-2 diamond of sorts. But I doubt we'll see much of that again as it's ultra reliant on high octane attacking fullbacks, which whilst not being beyond Walker is a stretch for Delph. Losing Mendy hurt us in that regard.
Basically, whilst I'm 100% convinced Silva will turn out wonderfully whatever the case, signing Sanchez in January would propel him into more regular gametime due to the balance having two somewhat similar but opposing footed players would bring.