Even if you stay downtown for the convenience of being located near the festival do yourself a favor and get the hell out of downtown to hang after the shows. There isn't jack shit to do after 5 pm in the loop and it is largely lame as fuck.
WORD
The area around the park is a glass curtain jungle after the last show of the evening. Do yourself a favor and wiki chicago neighborhoods, and pick one that sounds appealing to you-- then find a hotel near an El stop.
Oh, also, are you planning on bring around Finder?