Both suggestions are 'right'. You need to mount a large antenna outdoors, clear of obstructions to accomplish the goal of receiving the top five networks. The HD7082 (or 7084) on a rotator solution gives best selection of signals. the Fixed aim HD7696P gives you channel-surfing-friendly access to the range of networks you asked for.
Your TV Fool report is based on the default antenna height of 10'. As you go up in height, I would expect conditions to improve. You can run another report at 25 or 30' (up to 500' if you like) to see, but the results of your tests have proven indoor reception is not going to be satisfactory. If you run a new report, you may find that you can use a smaller antenna.
As I look at the aerial view of the Iowa City, I'm concerned about the possibility that trees may be a factor. You'll get far more reliable reception if you are able to avoid aiming the antenna into a tree. In a perfect world, you would be able to mount the antenna above the tree tops. Rather than suggesting yet another antenna choice, I'll simply encourage you to consider that mounting location and height are likely the single most important factor affecting reliable reception.
There are various suppliers of mounting hardware to choose from,
http://www.3starinc.com/
http://www.solidsignal.com/c/product...ennas-supplies