Well, the first thing I'd do if I was looking to build time in that area is to fly from Green Castle (IA24) - Cheapest planes I've ever flown. They don't look great, but they are properly maintained. The Citabria runs $70 an hour, I think the Ercoupe is even cheaper. The "expensive" plane on the field is the Arrow at $110/hr. It's also a great community, and you can head down there for a steak dinner on any Wednesday night for about $7 and talk about airplanes.
That said, in 200nm from KCID you can do lots.
1) Two of the best airport restaurants there are are approximately that far away: Pilot Pete's at 06C (Schaumburg, IL) and
2) Final Approach at KSBM (Sheboygan, WI).
3) If you're more into breakfast/lunch, The Jet Room at KMSN is good but closes at 2 PM.
4) Be sure to stop in for the every-friday-at-noon fly-in lunch at 68C. There'll be lots of neat airplanes and other flying contraptions there to ogle, too.
5) EAA museum at KOSH. (Park at Basler, they'll give you a ride over and back.) You can spend all day here... I've been there 3 times this year (usually between lunch at 68C and dinner at KSBM) and still finding new stuff to look at every time. Completely missed the big hangar full of WWII birds the first time...
6) It's a bit farther than 200nm, but Door County is a great place to spend a weekend. If you like camping, 3D2 is close to Peninsula State Park. Washington Island (2P2) is cool too - Bring a bike and take the boat to Rock Island as well. Also, get a Fish Boil - The local cuisine. (Search for it for more details.)
7) As mentioned before, 6Y9 on Labor Day weekend is a LOT of fun, and you'll get to meet some of us in person. So, well worth busting the 200nm circle for.
8) In late September/early October, fly to Y72, then north to clear the R-area and east to ISW. You'll not only get to see the fall colors in the trees, you'll get the added color bonus of large fields of red as they're harvesting cranberries in that area. ISW also has free smoothies (at least they did last I was there).
9) There are frequently safety seminars at KSTE - Call up Am I High Aviation (yeah, that's really their name) and see when they'll be. They show up on my AOPA emails as well.
10) La Crosse is right on the Mississippi and there's a ton of restaurants a courtesy car away.
11) I'll use this space to second others' comments about KJVL, KOVS, KPDC.
12) The weekend after Labor Day at Brodhead (C37) is an antique airplane fly-in. I think you need to have a membership for this one, but it is VERY cool if you like vintage airplanes - Almost like a mini-OSH but remove everything newer than about 1950.
13) Watertown KRYV - Walk straight out of the FBO's driveway for a block, cross the main drag and just on the left is a restaurant called Steakfire where you grill your own steak. Good food, good prices. I don't fly here much simply because it's too close to the home 'drome.
14) On a sunny summer weekend day, fly to KAMW or KHXF and get yourself a glider intro flight (an even cheaper way to build time.
)
15) Burlington, IA KBRL, stay away from the SIDA area (red line on the ramp), walk out of the FBO and take a left, head to the Tender Trap which will be on the corner.
16) Go to Lancaster 73C and jump out of a perfectly good (well, maybe) airplane.
17) Head to Mexico... Uh, Mexico, MO KMYJ and tour the Zenith Aircraft plant.
18) If you can save money by buying cheap fuel - KRDK, KAWG, 63C, KCLI are pretty reliably cheap.
