I think one of the beauties of Sanchez, if we can eventually get him, is that he can play anywhere across the front line but also drop a little deeper and cover one of the positions Dave and Kev own. I don't think that should be hugely to the detriment of Bernie, who has time on his side to build a long fruitful City career. If Pep can rotate more and vary things more without a drop in quality, players like Bernie and Gundo may benefit from having Sanchez here.
Possibly, & BS is such a talented player, but when Sane came on v Newcastle, imo there was suddenly a feeling that Newcastle were in iminent peril, if they lost the ball, which isn't there when BS plays & tbf, imo wasn't there whe Silva & Nasri played either, great as they were. We strike terror into opponents now.
Imo Sterling & Sane are now a blueprint for footballing terror which Pep has discovered through trying different options, & much as I love DS, if he was playing in place of Sterling or Sane, (assuming both are on form) I'd say we were a 'weaker' team, than with those two in it. Not necessarily so, with Sanchez up there, as he can still go direct like Raheem & Leroy do. But Bernardo, DS, even KDB, in a front 3 position, is now usually a step down in attack imo.
Of course that can change with the incessant bus parking negating their pace, but even then both Raheem & Leroy tend to shoot & run in behind more too.
As it stands, Sanchez would be a great alternative to either, or to Jesus/Aguero, but if Pep decides he can play as an alternative to DS & KDB, I think both Bernardo & Gundogan may have a problem.
Don't forget, Pep wanted both Sanchez & Mbappe. Maybe the idea wasn't for both to play in the front 3.