Yes, they have more indoor seating than outdoor. The theming in restaurantosaurus is IMO is the best for any disney restaurant. It's set up like young dinosaur diggers use this CS as a recreation area. Just so you can be sure here's Tusker House's and restauranosaurus' indoor seating.
For portion size and tastiness, I recommend Tusker House. Surprisingly, we had never eaten there before our last trip and I was pleasantly surprised. I had the salmon with rice anda green veggie (maybe green beans?) and it was very good. DH and older DD had the fried chicken sandwiches, pretty standard but large portions. Younger DD had the rotisserie chicken leg kidsmeal. It came with mashed potatoes and I think applesauce. She ate it all (wish there was a two piece available ) then helped with my salmon and rice. Other thing is that since AK has no table service, Disney Dining Experience members get the discount there.