You could be right, Biliew would have had an easier time this year if he played the 3 based on his existing skill-set and physical maturity. But I doubt that would have resulted in minutes for Biliew. Curtis Jones is an above average Big12 wing- especially for a 6th man. And then throw Watson into the rotation at the 3 and not many minutes for Biliew.They are forcing him to play as a big which is not his skill set, nor is he big enough to play as a big.
At 6'8- it seems like Omaha has enough size to play post in the modern game. As a 5, Omaha's not a great defensive matchup against certain teams which have a traditional center like KU's Hunter Dickinson. But he could play the 5 against most Big12 teams. And obviously play the 4 against anyone. Not having seen Biliew play enough minutes at the college level, not sure if he has a consistent 3 point shot to play wing against Big12 teams.
Obviously, the staff has a plan. I would think they view Biliew and Momcilovic as complimentary players at the 3/4 spots. Momcilovic more of a 3 on offense and 4 on defense. Biliew as a 4 on offense and 3 on defense. I think both guys will naturally mature and put on some weight and strength is offseason.