Ideas for long flight to midwest

We have a Cherokee 140 and have flown to OSH twice.

So this year we decided we would try instead to fly from California to
North Carolina (FFA)!

But scheduling problems cut two days out of our schedule, making the east
coast a bit too much of a stretch.

So we're planning on leaving Friday from CMA, going east to Amarillo on the
first day. After that... some combination of where the weather is better
and what is interesting. We're thinking we'll go east of the Mississippi,
perhaps Ohio, Kentucky, etc.

So my question for you midwesterners is: where is interesting to visit? Any
great airports? Any good museums? Anything noteworthy? We're pretty
flexible on where we can go, so give us some suggestions and I'll post a
trip report in a week and a half or so!

Tim Long
PA28-140
Camarillo, CA