For me, the last two episodes were the best in my book for ending an already great series. As a child when I saw it in the 80s, the idea I got from it, that it was possible to actually see a Fraggle if "touched" by one and that no matter where you go, there was a chance the Fraggle hole would be there if you believed in the magic. Although we know in real life it'll never happen, but when Doc finally sees Gobo, I couldn't help but feel all excited inside that it finally happened.
As I said in another post, it didn't have to stop with Doc discovering them, if the show had continued, there was a whole new door of possibilities for the show to continue. I hated it took 95 episodes before Doc finally got to see one, while Sprocket gets to see them, play with them, and even explore their caves. Lucky dog.
In no way would I say the show lost any of it's magic or fraggle feel, it's just impossible in my eyes. When it ended in Change of Address, it left me wanting more Fraggle Rock more than ever, but since that was their finale, I knew the magic would have to continue in me and it's fans.