Be advised this is my opinion only and worth exactly what you are paying for it!
Advantages of caravan:
Route planning done for you
Tons of daily social interaction
See the most places in the least amount of time
Security of tail-gunner to call for help if you break down in the middle of no where
You will see all the major shows and other attractions along the road
You will stay in the nicest RV Parks
Disadvantages of caravan:
All the above with the exception of the tail-gunner
We took 4 months to drive the Alakan Highway and around Alaska in 2012 and 2014 solo. I am pretty handy with maintenance tasks and we are both anti-social so the caravan was not an option for us. Plus being able to spend 5 days each in Teklanika, Soldotna, Homer, Ninilchek, Valdez, and along the haul road to Deadhorse was not an option on a caravan.
As previously mentioned, it is pretty hard to make that trip and not be impressed. Just pick one and Do It!