Thanks, all! These are great suggestions and I need to do some more research and run them by H.
We have done Deep Creek and the Finger Lakes, though it's been years. I'd like to go back someday, but probably prefer some place new.
For those of you saying Michigan, can you name some particular towns I should be looking at? I've always wanted to go that direction so that might win.
We've been to MI a few times. If you do the western shore, we really loved South Haven and Saugatuck. South Haven had a wonderful beach and a cute downtown area.
Possibly my favorite MI trip was when we did Mackinac Island and then the Leelanau Peninsula. We stayed near Suttons Bay, visited a bunch of cute towns on the peninsula and visited Sleeping Bear Dunes. We don't have kids and a lot of trip was winery-focused but there's some nice beaches, the national lakeshore is fun, and Mackinac Island was fun with biking it, etc.