which of those is a marquee win? maybe wisconsin? but that's using the word "marquee" rather loosely. none of those teams were ranked when Iowa played them. I'd say some of those wins look a bit better as the year went on (ISU, wisky), but none of them jump off the page and make someone say "oh this is an impressive win right here".
and you can't have it both ways. you want to count minnesota and Illinois as resume builders by saying they're quality high RPI wins, but at the same time you want to say that they aren't really all that great and that they themselves don't have very good resumes and that Iowa should be in the tournament instead of them. which is it?
another thing you need to keep in mind. NCAA tournament selection isn't necessarily about fairness. it's about who the committee sees as "qualifying" and having a good chance at making a run. that gives teams that have shown they can knock off high seeds a leg up (IL and MN both beat #1). Iowa's low scoring boring brand of ball also won't do it any favors come selection time if they are in fact in contention at that point.