CHA certainly has its design flaws, but I think most of the atmosphere issues come from the people in the seats - or lack thereof. For whatever reason, the student population in the last 30 years has never really embraced Hawkeye basketball fandom the way they have football. Cheap or free tickets and better seats would be a great start, but I think it's going to take multiple seasons with high-level success to really turn it around. Every time we have this conversation, people like to point out how inconvenient it is for students to get to CHA. I reply that there are multiple free Cambus routes from both the east and west dorms that drop them off at the front door. But they never seem to like that idea, so in my opinion they are looking for excuses and reasons NOT to go. They simply don't care enough to make even the most minimal effort, and I'm not sure how to change that. Iowa basketball has to become THE thing to do for the student population like football is. That's not something that's fixed easily, IMHO.
And that's not even to mention all of the non-students who silently sit on their fat arses and leave with 5 minutes to play regardless of score.
Bottom line....it's a cultural issue, not a structural one.