Great review, my one quibble is that I agree with CR that Ultimate Alien WAS indeed even worse than Alien Force. I'm not sure if you watched it or not, but you only touch on technical surface details that seem like good ideas. However, they were executed poorly, and all the faults of Alien Force were made that much worse. Ultimate Alien is the worst Ben 10 sequel, while Omniverse is the best, but they all pretty much suck when compared to the original show (mainly since the creators/writers of the original show had NOTHING to do with any of the sequels!)Oh, and Ultimate Alien's second season actually brought Elena and the Swarm from this movie into it, fusing them together making Elena the new queen and totally yandere for Ben. It was one of many misogynistic stories in that season (poor Julie and Charmcaster also really suffered.)
I'm only up to the first bit of Season 3 of Alien Force, but I think that's enough to say how I feel about. While I like the orginal series, there was room for improvement as Ben suffered from Aosep Amensia and could be annoying, and the show could have been a bit more complex, as it teased in some episodes. Alien Force was actually a good idea, and so far, actually can pull some pretty good episodes, when it feels like the writers are trying to do more complex and interesting stories.Other times, it's bland with the characters being dumbed down, and making Kevin a good guy was a bad idea, and the shitck with him and Gwen was...bad. So it's a mixed bag. Not quite bad, not quite good either. (Also, that Sigh moment is made worse by how Gwen is almost never that dumb otherwise)As for the live actions films, both are honestly not horrrible, but not very good either. The first was just dumb and rushed, and this focuses on a plot I don't care about because Elena has no character at all, yet we're supposed to care. On the other hand, it's well made for what it is, and sometimes it's harmless enough, but overall...yeah, not good.So yeha, Ben 10 is mixed for me so far.