I will start by saying that this season has really disappointed me a lot. The amount of "Deus Ex Machina" present in practically all the chapters is something that I have never seen in SAO. Everything is resolved by "the power of love (or friendship)". In that sense, I think the plot argument is 1/10.
It's unfortunate, since they had a good story base in the first few seasons, but every time I was watching a chapter I felt like everything was going to hell.
On the other hand, the music remains almost the same from the previous seasons, the studio loves to recycle the same songs over and over again. So I would give the music a 5/10.
The animation is really good and without considering the Deus Ex Machina, I think it would deserve a 10/10. But, on many occasions I felt that this animation was unnecessary, because as I said before "The power of love" takes you out of context. It is never explained where they get these incredible powers, they simply want to amaze you with their animation capabilities. In that sense my final verdict for the animation (And because I think it is wasted a lot) is an 8/10.
On the characters side, there are characters who literally do not add anything to the story, such as the Chinese who (mini SPOILERS) entered the game and who only dedicated themselves to seeing how others killed each other. I think they wasted a lot of content and didn't know how to handle the desires and feelings of the characters either. I give a 4/10 to the characters.
I did not enjoy this season as I used to enjoy SAO, I think it was disappointing and that it did not deserve the fate it was given. In enjoyment I give it a 3/10.
Overal this season is 5/10. I don't think this season deserves more than that.