I did like the final scene with the truck. We don't really know how Merlin's been living his in the tween time. He's might have had many family's of his own since then and come to accept the cycle of life and his part in it and keeps a periodic check apposed to a constant vigil waiting for the future time to come. And then there's Athusa. With Morgan out of the picture, they could be hanging out.
All and all I liked the show. It didn't leave me hating them forever and it's going to be interesting what stuff the production team have in mind when they go it on their own.
Would have liked a bigger battle between Merlin and Morgana, but I guess that would have cut into the reveal time and they did allow a proper enough time for Arthur to go through all the proper stages of finally getting what Merlin was all about (the person, not the show).