As Matt said, if you're new to wheeling, it would be good for you. SLOHV is laid out very well and it is hard to get lost, but you CAN find a remote mud hole or two, right Matt?
Jamborees are really geared towards new wheelers who want to experience it in a family environment. The guides, of which I am one for that Jamboree, are there to help you around the park and to make sure you minimize your damage while having fun. It can be slow at times, depending on which group you wheel with (beginner, intermediate, or advanced).
From a personal POV, if you live close (I live 1 hr away in Huntsville), it may not be worth it to spend $250 for THAT jamboree. Gateway to the Cumberlands is private land and only opened up for that particular jamboree. If I were paying for a Jamboree, I'd pay for one further from my home (Moab, Ouray, Texas Spur, Cumberland would likely get my money).
And yes, hotel is separate. You could camp out at Smith lake though.
Other Alabama parks include Morris Mountain, Greyrock, and Hale Mountain.