I have had a bit more time to think about this question and type up a fuller answer now.
I will interpret the question as putting together the best 13-man scholarship roster that I can plus one or two more spots for walk-ons to give you the full roster for the team.
For reference, these guys won all-Big 12 honors under TJ.
Brockington (1st, Newcomer OTY)
Hunter (Freshman Team, Freshman OTY)
Kalscheur (2nd, Defense Team)
Holmes (Newcomer Team)
Lipsey (Freshman Team, 1st, Defensive Team 2x, 3rd)
Gilbert (2nd, Newcomer Team, 3rd)
Momcilovic (Freshman Team)
C. Jones (1st, Sixth Man OTY)
Jefferson (2nd, Newcomer Team)
STARTING LINEUP
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Lipsey (the best PG of the TJ era, no argument otherwise, the straw that stirs the drink)
Brockington (won first-team all-Big 12 for a reason, simply a terrific two-way SG)
Momcilovic (no argument whatsoever for taking a shooter this good off the floor)
Jefferson (obviously on an AA campaign right now, easily the best forward of the era)
R. Jones (already litigated, but he's the perfect complementary piece to these four starters)
BENCH
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Gilbert (the de facto backup PG and quite the two-way SG even if Brockington is slightly better)
C. Jones (thought about starting him but kept him in his preferred Sixth Man role on the bench)
Kalscheur (absolute defensive stopper and underrated on offense during his senior year)
Toure (needed one more guard... ran through Holmes, Heise, Grill, Hunter, and even Batemon, but Toure is the best of the group so far and obviously has room to grow... freakish defender)
T. King (the roster needs another PF or two behind Jefferson, and Tre King was the best of 'em)
Kunc (might not play much with these guys around, but felt like a good locker room guy and depth)
Ward (restores the R. Jones/Ward rotation that worked so well during TJ's best season so far)
Buchanan (might as well have three big men if we're going as deep as 12 here)
WALK-ONS
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Kelderman (is good enough to earn a scholarship and see some Big 12 minutes in duress)
Hawley (duh)