Yes, there are a number of things that you should pay attention to because a big team will lose balance if many of their core players leave in this summer's transfer window. Manchester city just made their history last season by winning the treble winner. So there are several steps that pep must anticipate to balance their strengths in the next season, where he must be able to persuade star players not to leave in this transfer market.
Indeed pep guardiola has some stock players but if some influential players in the depth of their squad leave in this transfer window then it is very likely that manchester city will also lose its best form next season. Therefore I think pep guardiola has to hold Walker and Silva to stay with them next season.
Bernardo Silva and Kyle Walker deserve to be kept because of their performances, but I don't think Manchester City should ban Ilkay Gundogan and Riyad Mahrez from going to other teams. If possible, Pep should persuade both players to stay at least for next season, but if he has to choose one for one reason or another then I think Bernardo Silva is the most deserving.
Besides, I don't really believe Manchester City will lose the balance if the two players leave before the new season starts. Pep Guardiola has a large stock of players to put in the shoes of the departing players, so I don't think it's that big of a problem. I also want to ask like with BITCOIN4X, what are you worried about from Manchester City if Walker and Bernardo leave?
I think every Manchester City player has great artistry. Everyone works hard. Besides, the coach of the team is a person of extraordinary talent, I think the team deserves to win more titles under his leadership.