It's a great little lake, but sometimes you have to drill a lot of holes to find consistent fishing, so it helps to have electronics and a good auger.
I always look for evidence of weed edges when I ice fish Summit, even late ice.
The few bluegill I have kept out of Summit over the years have been chock full of little snails, if you're looking to "match the hatch" with bait. They looked like they're used to eating well.
Nate