Bailly will never be a first team CB.
Tuanzebe is a big risk.
Jones and Rojo need to go, I see no one arguing anything else. Smalling is likely to be sold, as he will actually bring in some funds. Bailly might get another year, but really needs to be offloaded.
"Never" is a strong word, but it is fair to acknowledge that he's injury prone. Yet Bailly has played well when fit, and we can't really say that a head injury is proof of anything. I wouldn't close the door on him just yet, but at the same we can't bank on him being fit for an entire season.
You're spot on that Tuanzebe is a big risk, yet we can see fantastic potential and after double-checking just now he's still only 22. Big risks can yield big rewards.
After we do offload Jones and Rojo -- not really sure yet what to do about Smalling, who might be agreeable to being a squad man for one of the biggest clubs on the planet -- what we're left with is the decision to spend a modest 20-30 for a decent CB and allow Bailly and Tuanzebe to progress or to spend 60-70m within a 150m budget for a truly top CB that only allows one other significant purchase. Easy call -- spend the more modest sum on a solid but not top class CB so that we can bring in another midfielder to replace any one or two of Lingard, Mata or Pereira; or for me, a successor to Matic, who just can't deliver top performances next season for more 30-35 matches in all competitions.
If we had 200-250m to spend, then by all means bring in the biggest names we can find for all positions of great need -- RW, DM, CB and backup AM -- but I seriously doubt we'll have that kind of cash to spend in this transfer window.