Claudius I don't see a lot of clear upgrades on Martinelli. I see a lot of potential upgrades but they are risky. We need more depth in the wide areas and Martinelli has played both sides this season, letting him go would be an awful move unless someone offers truly silly money. We're never going to sign someone to displace Saka so you are looking at CF and LW to improve this summer. I think we should get someone like Williams who is one of those risk signings that could be better than Martinelli but might not, and might take time to adapt, etc
We have a similar situation at CF, although I think there are more possible upgrades there and the situation is complicated by the likelihood that whoever we sign will have start the first few games of the new season as Havertz may still be recovering from injury. I really want a more natural CF than Havertz who is of a high quality but we will still need Havertz available for us.
We've had our season ruined by injuries yet again and that is partly a depth issue. We need more quality loaded on top of whats here now, not instead of it.