I loved it, I think. (It needs a rewatch for sure.)
I loved that Joan, Roger, Pete, and Peggy all got fresh starts that felt in line with their character arcs, though I'm not sure I completely buy Reformed Pete Campbell. Joan gets use her hard-won payout from McCann to become the boss she always should have been. Roger becomes a grownup, finally - his line about Kevin being a "rich little bastard" was my favorite of the night - and finds a woman who is his equal in age, intelligence, and emotional instability. Peggy and Stan felt like audience wish-fulfillment, sure, but I like how Weiner bookended her story with office relationships in which the power dynamic is completely flipped. I also buy her staying at McCann because Peggy is, above all else, practical and risk-averse, especially with regard to her professional life.
Don is the only character without a finite ending because he's the only character who never grows or changes. He's Don, and he'll always be Don. You can strip him of his suit, his office, his car, even his name, but he'll always be the survivalist he was in Season 1, always looking for the next Big Idea (or con, depending on your view of him). Every setback is a jumping-off point for Don, building on his need for artifice: Korea made him Don Draper. His divorce from Betty pushed him toward Megan. Getting stranded at a hippie retreat (probably) inspired the Coke commercial. I still love McCann's president's perfect description of Don as the "white whale" - he can destroy everything around him, but it doesn't matter, because he's the prize everyone wants.
I'm going to miss this show.