As for hotels, most of our experience has been with larger chain hotels (Sheratons, Hiltons) - but we aren't married to that style hotel. We would like someplace where we aren't necessarily another number - years ago I had stayed at some hotel right on the river (maybe a Hyatt?) that was massive, and that is too large by far. As for budget, we'd like to keep it under $500 - the overnight we have planned seems to coincide with many hotels being unavailable or very expensive. $500 is what the Westin River North is charging.
For food, we have no restrictions on cuisine or budget. We were engaged after a meal at Frontera, and we will definitely go back there. We'd love to go someplace even "nicer" or "more special" - when I lived there, Charlie Trotter was someplace many of my friends went for special occasions, so something in that vein 15 years later would be appropriate.
I would love to extend my trip to Sunday - but alas, my high maintenance children require our presence back in MSP. So think of this as a blow-out romantic-ish getaway where we condense the awesomeness of Chicago into a tragically small period of time.