A description from the extra inch podcast that's also been used here before is that Ange's system requires all the parts to be working to be good. Similarly to a lot of top coaches like Pep, Klopp and Conte.
To me a bit different to for example Mourinho (when good), Emery and other (also top coaches) who are more "no matter what happens we'll be in a situation to grind out a result" with their systems.
We have been assembling this squad for quite a while now as you say, we have spent quite a lot of money. But we have gone for a fairly long term squad building approach. If there were no further changes (hypothetically) this squad should be better in 3 years than it is now.
When injuries hit hard and the fixture list gets congested that will leave an Ange team with this squad building approach suffering. Probably more than say if we had Emery in charge for example.
I like that approach. I think that's our best way to build something that will be special. And wanting real success from our financial situation and the starting point pre Ange we have to build something special I think. I think the ceiling over time is higher with that approach.
That's how players like Gray, Bergvall, Spence, Moore, Odobert etc will learn to play well in this system. That's how players like Udogie, Johnson, Dragusin and Sarr can take further steps playing this system. Not abandoning it when things get tough, but sticking to it, learning and developing to become key players for us.