I am beyond grateful we got this conclusion after basically a decade of dickteasing. Good on Adult Swim and Cartoon Network for bringing this back.
I feel like the season overall had some meandering parts that could have been better spent elsewhere, but overall this was more than a worthy conclusion to one of the most epic American cartoons of all time.
Gurren Lagann did come to mind with the end, but I would still say Samurai Jack's made more sense than that (the logic behind TTGL's ending was just a load of crap in light of everything that preceded it).
Yeah, the season really need 3 more episodes or so to hell flesh out certain other aspects (this could of a been a two episode finale) like Ashi's mom's death which feels like they threw in because they needed to tie that loose end.