I get your point and don't disagree, however I do want to point out that if we only buy Ederson +1, then our starting midfield is Mainoo +1. In that case when we play twice a week, then the second game we play Ederson + youngster, or we need to rotate Mainoo/+1 with Ederson. Therefore, Ederson will see a lot of playing time (what I think is not a good strategy) and +1 player basically needs to be ready to start. And all of that is assuming we don't have any major injury, which would mean Ederson is the starting midfielder.
I still think we need 2 more midfielders. Either that or pull the plug on Ederson deal, and spend what we wanted to spend on 3 players on 2 midfielders and sacrifice striker/winger.
We have absolutely no depth in midfield as things stand, we are better in other positions all over the pitch.