I understand the reasoning for our transfer policy having been like this in past seasons. When we had a weaker team and smaller budget it made sense to sign quality players on the cheap wherever we could find them and regardless of role to raise the level of the squad to a certain quality. There wasn't really a particular style of play in mind we just signed the best we could and let the coach figure it out
Now that the team has significant quality and depth our efforts should be concentrated towards specific positions with an idea of how we want to play in mind. No more signing Emre Cans and Matuidis to play box to box roles where they are expected to contribute beyond their qualities.
This summer our key target should be an all action CM. Someone of serious quality who can contribute a well rounded game without glaring weaknesses (no Pjanic or Matuidi) and it should be someone of serious quality. 2nd should be a CB of quality to be at least a 3rd CB and someone who is good enough to cover/ rotate in without being a liability.
If these needs are met, and we still have funds left, then we can look at signing prodigiously talented portuguese 19 y/os but only after some glaring weaknesses in the team are addressed. Before that we should not be buying any more attackers.
I suppose we also can't overlook Alex Sandro's shit form either. I am sick of him. I think we may have waited more than long enough for him to recover his form, at this point it might be time to sell and look for someone else.
TLDR, address team needs and IMO that means prime Vidal over new Ronaldo