Personally, I liked the episode and believe it to be one of the best for a long time however it was way too abrupt and short to warrant the wrapping up of the All Out War story line which started multiple seasons ago.
The fight scene between Rick and Negan was amazing, especially the few moments when Rick mentions Carl which made Negan emotional - this scene is what made the episode likeable for me as up until that point it all seemed rushed.

The bits I didn't like about the finale was the fact that for once it doesn't give us much to go by with what next season will be orientated around - the only path left open is the whole Maggie, Jesus and Daryl wanting to go against Rick which imo will be a shortlived storyline being only so many places they could go with that.

I believe Season 9 will be based around a group known in the comics as the 'Whisperers' which have been hinted briefly now for the past few seasons however who knows considering the show doesn't tend to follow the comics.