I go to Chestnut almost every weekend, including this season. The snow has been pretty awful all season, but of course that's a reflection of the weather and not Chestnut. Even still, they have a pretty decent base built up and even some monster jumps on one of the blue runs as part of a contest last week. If you're going, definitely go during the day when the snow is softer/slush because if you go on a night that dips below freezing, you're going to have sheet ice. And even worse, if it's windy it will blow all the loose snow off the runs and you will be riding literally on bare ice.
Devil's Head and Cascade are usually much better choices than Chestnut. I was at Devil's Head a couple weeks ago right after a small dusting and it was pretty decent, but you will never get to ride fresh pow there because they groom 99.9% of the hill immediately after a snowfall.
I haven't been to Granite Peak this season so can't comment.
Sundown Mountain in Dubuque is pretty good (at least as far as Iowa/Illinois is concerned) but it's smaller and shorter than Chestnut. The runs aren't as steep though, which could be a good thing depending on your preferences.
Unfortunately all of my comments are moot now, because most of these places are closing in just a couple weeks.