Some Places More-or-Less on Route
Welcome back.
The first thing to note is that while ten days may seem like a lot, a full four of those days will be taken up with driving a fairly direct route through the places you mentioned. If that ten days also includes flying days, then you're down to just four days (maybe a little more) for actually doing stuff. So the first thing you'll want to do is get your destinations laid out in the most efficient order. That would be Chicago, Pigeon Forge, Lynchburg, Nashville, Memphis, St. Louis, Chicago.
Now, besides the cities which I assume you've looked at and know what you want to do there, where/what else might be worth a stop? In Kentucky, Mammoth Cave would probably top my list. If you do decide to visit Mammoth Caves, there is a small two-car ferry across the Green River that might interest you. I'd also try to include some of the Appalachians by using US-441/US-74 from Pigeon Forge to Chattanooga and then continue on I-24/TN-55 to Lynchburg.
In addition there are more Civil War battlefields in the southeastern portion of this trip than you can shake a stick at. So let us know what, if any, interest you might have in visiting a few.
Two last places where I'd recommend at least a short stop. First, seeing as how you're from the west coast, is New Madrid (pronounced 'New MAD-rid') just off I-55 on your way between Memphis and St. Louis. This is the site of the largest earthquake to be recorded in the United States (1811). And second, Hannibal, MO might not be too big a detour.
AZBuck
Music and Attractions Other Than Dolly Parton
There is, of course, lots more to do in Pigeon Forge than just go to Dollywood. That's true of areas around most major amusement parks. There's also plenty to see and do in Nashville and Memphis. Also in the Pigeon Forge area, and during your travel time frame, is the annual Gatlinburg Songwriters Festival, while Memphis' music scene is more Blues oriented than Country.
AZbuck