RE: your final comment. The reason Salisu and Bednarek have a high number of interceptions is because they are clearly being instructed to press the attacker at the earliest opportunity rather than jockey. It's a high-press/Ralph thing, which tends to backfire frequently. Anybody with eyes will tell you that if it wasn't for Romeu playing DM this season, we'd have got relegated. He has been an absolute force. It's a must that we keep him (I've heard rumours suggesting he may be leaving too). Diallo is no way ready to step up in Romeu's place, and we need far too many other replacements before we sign a DM.
I'd also be keeping Stephens and Redmond as they are both adequate squad members.
It's one aspect of Ralph's high press that I dislike: Romeu was good, but he also wasn't the screen we need in front of our defense, because with a 4-2-2-2 we don't really have one; both midfielders need to push higher up the pitch to take away space in the center of the park. Poch played a narrower press, often with a defensively-competent player (like JWP, or Davis) in a nominal wide role, but working to compress space through the middle out of possession, which in turn meant that one of the CMs could play deeper as a screen for the defense, with the fullbacks pushing further to deny space down the wings.
So we could really use a Wanyama, but we also need to play in a fashion that would actually allow them to play as a Wanyama. Our press, to the extent that we play it, is really reliant on the forward players disrupting the initial attack; if they fail (and our attacking players haven't been terribly good at it for the past few months), we're outnumbered. And if the midfielders step up to try to deal with balls played through the middle and fail, the ball gets on our CBs in a hurry, hence the interception stats.