Obviously Iowa should be a very good team, but I think people are inflating Iowa's team from last year due to Garza's individual success. I'm not sure what they would've actually been seeded, but NET was #34, which equates to a 9 seed. Obviously they don't get strictly slotted, but I doubt a variance of more than a couple spots from NET.
Of course they have most everyone back, and getting Bohannon back helps, but I don't think there are any other additions of note.
If this was 20 years ago, I'd agree that teams that brought everyone back typically made a nice jump relative to the competition. That isn't so much the case any more. Transfers help teams reload with proven, experienced talent. Also, it used to be that only the top freshman were ready to come in and play well in major conferences. Now freshmen are way more ready to contribute as a whole. Lastly, I don't see any guys on the Iowa roster that are loaded with talent but just need to put it together to make a huge jump. There's a fair amount of room for Wieskamp to be better, but for the most part it seems like most of their guys are close to their ceilings. That's obviously a good thing and a compliment to their players, and Iowa will be a good team. But going from a 8-9 type seed to a top 5 team seems like a stretch.