Chitown's offering are somewhat date-dependent. Ravinia is a favorite, but it depends who is playing, just north of the city. As you might know, it is a beautiful park with outside seated and lawn concerts from the CSO to rock. Listeners bring food, wine, candles.
Same thing with Grant Park/Millenium Park Festivals. Blues, Gospel, Jazz.
Long walks up Michigan Ave, window shopping, always choice.
For books, Hyde Park.
On the expensive end, options are endless, but out of my league. For pure romance and a gorgeous look at the city, there is the Signature Room on the 95th Floor of the Hancock Building. Best view in the city.