In terms of replacing confirmed outgoings of Thiago, Matip, and Adrian these can be possible realistic signings (below names just based on rumours I've come across) -
3rd GK - someone like an Alex McCarthy. HG option
CB - Pacho or Hancko
Mid - Koopmeiners or Weiffer
I feel LB and any FW signings will depend on outgoings only.
I'm personally not too enthused about these options to be honest, they look like solid squad options
Yeah, they do seem more like squad players than genuine improvements to the team, though maybe I'm just underrating them.
I think we can probably cope without buying any squad players this year. We have people like Jaros who could perhaps be 3rd goalie after his year at Sturm Graz. Mrozek and Davies seem well-regarded goalies too.
Quansah's rise, and Gomez going a couple of years without significant injury, means we have excellent squad centrebacks already. Van den Berg may stay as well. At centreback I think we only need someone who is at least as good as Konate, but with a better fitness record.
Similar in central midfield. the return of Bajcetic, alongside our other talented midfielders and the potential of our youngsters, means we have plenty of bodies who can play there. All that's missing is an absolutely superior athletic player who will start most weeks.
The fly in the ointment of all our plans, though, must be the contract situations of Trent, Virg and Mo. Ideally, they don't go on a free transfer next year. That means selling whoever we don't re-sign, and that means replacing the sold player(s) suddenly becomes the most important part of our transfer business.