It's all about attitude
Let's face it, when you stay at a three-star chain hotel, you go in with certain standards. The hotel facilities itself met those standards for our family, but the staff absolutely blew them away. The room was clean and spacious for Chicago and the the housekeeping staff was great, tidying up our personal things (my husband said it was like my mother was traveling with us!) and laying items in the bathroom out on a fresh hand towel. Breakfast was exactly what you'd expect for a free breakfast, expect for the awesome oatmeal and fresh fruit-not fruit salad; fresh fruit.
The front desk staff was fabulous. Tracy and Cara planned the whole trip for us, and then told us about city passes which saved us a lot of money on the musuems, art institute, and skydeck. They hooked us up with trolley passes to save on cab fare from place to place. The kids loved the trolley, and even though it added a little bit of time to our commute, we had a lot of fun riding it and saved loads in cab fare. It was so nice to have someone welcome us back by name when we came into the lobby; That made it remarkable for me. Can you imagine asking for pillows at the front desk of a busy downtown chicago hotel, not giving a name or room number, and having them at the room 5 minutes later? 
Pros: The staff, location, value, free breakfast, hot coffee 24hrs a day, great environment for families- indoor pool, outdoor terrace
Cons: The noise- But this HAS to be expected. It's the city...it's noisy. It's the price you pay for being able to be so close to everything. Ask for earplugs. Valet parking...it can take up to 20 minutes for your car if they're busy when you call, but again, it's the city and it's to be expected that all things traffic related take time.