i misread your original post..sorry.
you can avoid Chicago metro but you'll either go waaay our of your way or thru some very sketchy neighborhoods.
me? i'd stay on I-80 thru the Indiana and Illinois suburbs to I-39 and then head north. if you time it right you'll avoid a lot, but not all, of the traffic. i'd want to run the stretch between where I-80 meets I-94 near Portage IN and Joliet IL between 10a-2p or way before dawn. you have a long drive. if you are doing it without stopping overnight you'll be leaving Ashtabula very, very early. if that's the case I'd just stay on I-90 and time it to barrel thru Cleveland before rush hour.
otherwise to avoid Cleveland consider...
Ohio SR11 south to I-80
I-80 east to the Illinois line
I-80 east to I-39
I-39 north to I-90 west
I-90 west to Illinois SR 14
you'll have one toll in Illinois where I-294 meets I-80. no cash taken...toll transponder or pay online after your trip is done.
safe trip.