I really enjoyed it, and I'm disappointed by the poor reviews. Surely this movie isn't on the level of The Incredible Hulk, Iron Man 2, or Thor: The Dark World.
I'd never read any Eternals comics so I went into this mostly not knowing what to expect, and honestly the movie didn't go anything like how I was thinking it might. For example, I thought Druig was going to be a bad guy and would, based on some stuff I'd read about Thena dealing with a mysterious mental problem, use his powers to control her as part of some evil plot. But instead Ikaris was the villain, which I didn't see coming at all. And I also thought the Emergence would have something to do with mutants, so while I'm mildly disappointed that it didn't (it's probably for the best anyway, Marvel has so many characters there's no need to rush the mutants) I quite liked the actual explanation for the event.
When I first heard that the Eternals were aware of Thanos and didn't do anything about him I was disappointed, but the reasoning made perfect sense to me once it was explained in the movie. The Blip was bad for business, in a manner of speaking!
I can understand why they changed the Deviants from fully sentient beings to mostly animalistic monsters, to be honest. I don't think it would have been a very good look if they'd kept the Deviants closer to their comic book counterparts and still had the Eternals going around massacring them. That being said, Kro was kind of wasted. Granted, he wasn't the primary antagonist we were expecting him to be, but I think it would have been interesting if he'd worked with the Eternals to stop Ikaris from preventing the Emergence. Oh well.
While I didn't really know much about the Eternals going into this, I'm more familiar with the Black Knight, so it was very fun to see Dane Whitman and the Ebony Blade (although, alas, not for very long.) I thought that was Mahershala Ali's voice at the very end, so I'm glad to see I was right about that; I can't wait to see his and the MCU's take on Blade. I guess this means we're going to see some form of MI-13 either in the movies or on Disney+, which could be fun. Hopefully that also means we'll get Captain Britain and the Excalibur team, too. In fact, I seem to recall Captain Britain and MI-13 being involved in fighting against the Skrulls in Secret Invasion...