I get it's a fun exercise to project future lineups, but in today's portal era it's kind of a waste of time in mid March. So many unknowns.
Luckily that specific lineup guess is almost certainly not going to be reality as it would really struggle to score.
Milan needs to stay at the 3. People's posts of him moving to the 4, don't understand just how physical you have to be to play it all season in the Big12. Milan is great at a lot of things, but being physical is not one. Also, IF he's coming back he's not going to completely change up his role. He and the staff would continue to focus on his ability to score - not bang down low.
TJ has a great foundation to work with on what could possibly come back, but they absolutely need to fill Jefferson's role in some way. Whether that's through spending big on 1 guy or splitting the production across a couple guys, moneyball style.
1. Toure(assuming he takes an offensive jump this offseason), veteran transfer, maybe Gray? - solid
2. Williams OR Batemon - solid
3. Milan?, Williams - if Milan back, all set
4. BIGGEST NEED - will need to spend big here imo
5. Buchanon, Pleta, DRK - all set
Pleta may be serviceable at the 4 if he has a big jump in the offseason on the offensive end, but can't rely on him as the primary option there. Him and Buchanon continuing to alternate at the 5 will be very effective. Anything you get out of the freshman, DRK, is a bonus. We all know, freshman bigs take a while to develop. Same reason I don't think we can rely on Jackson Kiss to come in, and offer much year 1.
They will absolutely need to find someone that can score and rebound (at least a 12 & 8 guy) - unfortunately everyone else is looking for this as well, so it'll come with a hefty price tag.
If Milan is back, he stays at the 3. If he leaves, I think you can make a rotation of Toure, Batemon, and Williams work 1-3. Williams has a bit more size - CuJo played this position in their 3 guard lineups last yr, and was slimmer than Mason. In this scenario I think you likely need to also go out, and get a playmaking guard because we just don't know what Williams is bringing yet coming off his injury.
Bottom line:
Primary - must have a plug & play transfer forward come in that can shoot it with some respectable consistency to maintain spacing.
Secondary - (a lot depends on Milan's status) playmaking veteran guard
Understanding these are big & expensive asks, but I think only needing a couple transfer additions for next year's team means they're already in a pretty good spot.