Those 4 you speak of… 2 new were signed and we’ll harvest 2 from the youths.
Besides… the 6 midfielders that left, barely count as 2.5 whole players.
I'd say probably 3 to 3.5.
Logically we should be getting one more midfielder really, but I think that would most likely be it.
If we were seriously intending to strengthen the defence too we would have moved Matip on (which IMO we should have done, but there we are. We didn't).