If people were frustrated with the defense last season, then I've got some bad news because the defense won't be better next season.
All the transfers Self brought in this season are somewhere between below average to they make Nick Timberlake look good on defense. Griffin was a part of a defense that was sub 100 in Kenpom's defensive ratings. Zeke Mayo couldn’t keep up with Summit League players on defense so that won't be better, and the day AJ Storr puts effort into playing some defense will be the first time in his career.
That's on top of what we already know about Dickinson's defensive abilities.
Elmarko has the tools to be a good defender so hopefully that part of his game starts to come together and McDowell needs to get better on offense so he's playable for longer stretches.
This is why I'll always say that a strong defense is more important than a strong offense. A strong defense with a weak offense will keep you in more games when the offense is off than a team with a strong offense, but weak defense when the offense is off. That said, you have to be really good at both, generally top 15 in Kenpom's offensive and defensive ratings to be a serious title contender. The anomalies in those rankings for title teams are teams that were strong defensively, but not as strong offensively.