I for one do not want to see the hills "bowled in". I think it's part of what makes Jack Trice special..it feels more "Iowa" to me by having at least some grass around. Plus it makes it a lot easier to take the kids to the game as I know that if they get crabby, we can just go to the hillside and let them run around while I can still see the game. So, count me as a "nay" vote for bowling in the stadium.
The north hillsides will still remain, and will likely remain for a long, long time, as any project that removed those would likely come after both the lower bowl in the south and the upper deck on the south end.