I actually preferred most of the episodes leading up to the finale, but I still thoroughly enjoyed the last episode. I was a little surprised to see the show end on such an optimistic note, given the sheer abyss of misery and sadness it often concocted - though Matthew Weiner has
said multiple times in interviews that he genuinely cared about the characters and wanted them to be happy, so I guess one could've seen that coming.
I think the Peggy/Stan story was, by far, the most satisfying aspect of the finale for me, but I was a huge sucker for those two from the get-go. The actors had phenomenal chemistry.