I agree with you that IU brought main pieces back. In pure % of most things like points, rebounds, assists etc. IU returns just a little less than Purdue, and Purdue returns about 80% or better of every statistical category.
They didn't bring in any elite or upper level freshman or transfers besides Bryant.
They have their starting 5, which is a very very strong and dangerous starting 5, and then 2 subs whose only positive is they are good at shooting 3s. Their freshman were sub top 100 players outside of bryant and Beilfeldt was a 6pt, 5 reb 6-7 center for a 16-16 team that won 5 games without Caris LeVert. He will not do much for them this year.
IU has 7 players that will hurt you and then nothing else and absolutely no size outside of bryant.
IU should be around 19, not 15.