Think Curbelos down year hurt Payne more than anyone else on the team. Payne is a big that needs to play pnr with an elite guard and illinois had far from elite guard play atleast in terms of pnr.
I actually don't think it was Curbelo as much as it was the offensive and defensive schemes we ran were a poor fit for him as a player. He's a player who has a lot of athleticism but would struggle at times with his positioning, awareness, and off the ball movement. As such, he'll have a hard time dealing with man-to-man (both offense and defense) as he needs additional time and space to operate, so you almost need to build your offense and defense around him to accentuate his talents while limit the weaknesses.
To make it work on defense, you probably need to play him side by side with another 6'10" highly athletic big in some sort of 3-2 zone, split the court in half, have the big on the side where the ball is be the primary defender who's goal is to funnel the player to the secondary defender big for the block. Two of the guards should cover the wings to avoid the open 3, and the 3rd should creep down slightly from the top of the key to both decrease the passing lanes while still allowing time to contest the elbows. This forces teams into midrange jumpers or floaters, or they need movement off the ball to get to the elbows and free throw lines, otherwise they will be either running straight into the secondary big defender or forced into a difficult passing window. In theory you'd want quick big guards for this. On offense, for the 3 guards you'd be looking for 2-3 slasher types who can hit a three at a decent rate and be willing to kick it out to the open shooter if the defense collapses on them when they slash, lob it up to one of the bigs making a run to the basket or just throwing stuff up off the glass looking for one of the bigs to crash and put in the offensive rebound. The only issue with this is that based on what I saw from Omar is that he doesn't seem to have either the nose or awareness to move off the ball to the hoop to crash for offensive rebounds or make himself available for lobs unless it was a set play out of a timeout.
So the question now becomes, if that's a style of play that in theory could bring out Omar's strengths, could Underwood have installed something like that and my answer to that would be only partially. Basically, Kofi is not an optimal pairing with him so changing the overall team defense to 3-2 is just not going to happen. So instead you'd almost need to run 2 teams out there- your 1st team is man-to-man, and your 2nd team is 3-2 zone. Now you'd rather not spend time teaching 2 offensive and defensive philosophies to your entire team, so humorously you'd almost need to make full line changes like you'd see in hockey. Based on those requirements you're looking at something like:
Starters (Man): Kofi, Trent, Damonte, Jacob, Plummer/Curbelo/Goode
2nd team (Zone): Omar, Coleman, RJ, Curbelo, Podz/Plummer/Trent
Where Plummer is your offensive weapon you put in and say try your best on defense, Trent and Andre could probably play either though I wouldn't want to wear Trent out playing much zone. But is this even good enough? Zone will have some defensive issues for sure, you lose flexibility as you'd rather not waste time teaching both systems, and you basically have to run split practices, plus if you have injuries, how do you get players to fill into the new role on the fly?
All in all, this is just too much time spent on what would be your backup big and just too cute and inflexible to be beneficial. Simply put, Omar transferring is clearly the best option for both himself and the Illini as he's just not a good fit for an offense built around Kofi or playing man, and as such we're not a good fit for him either. Definitely makes sense he's leaving and hopefully he can find a better fit for his skillset.
