If you're debating about a tour from Anchorage for one week I personally, would not do it. You can't get lost as there are only a few roads that a RV should travel. You basically just go in circle. Take the tour brochure and see what stops they make and do it on your own in your own leisure. Some places you may want to stay longer and some you won't even care about doing.
You really don't need reservations for campgrounds except for Denali Nat'l Park if you want to stay in the park itself or for the July 4 weekend. With a small rental you'll find spots to stay and you can even stay at a scenic pull-off for a night. You'll have a generator if you need it. Many folks do this.