Toby seems to be driven by what his agent (father) wants to do so I'm not sure that we can judge from Toby's actions.
Eriksen said (when at Ajax) that it was his dream to play at Barcelona (rather than Real Madrid) but if either come calling with a reasonable offer, there's not a lot we can do about it I think as there will only be a year left on his contract.
I think we need a LB, but not sure there's one we will get. Rose seems to be coming back to his old self although he'll probably never reach the heights on 2015/16 so it would be Ben who moves on, but I agree he may be kept on to cover LB/CB, although I think Poch wants to bring through one of several youngsters as a CB so it could get pretty crowded in the CB position.
Otherwise I agree with
kingdawson
list but I'd add Vorm (out of contract and replace with HG GK or Whiteman/Austin if good enough) and maybe 30 year old Sissoko (despite his resurgence) if we got in a good CM as its the last opportunity to get a decent fee, but again I think Poch would be just as happy to keep him if the fee wasn't large enough.