The thing I love is now people are looking at Covenant and saying "some old shit". Someone is always going to be unhappy I suppose.
I liked the direction Prometheus went. Nothing will ever be able to capture the isolated horror of the original Alien, so I thought focusing on the Engineers was much more interesting. In a way, it ended up being isolated in its own way. Instead of a cramped ship, it was an abandoned, barren planet. Creepy in its own right, it gave you that feeling of being insignificant. Kind of like the beginning of Alien on the derelict, which is my favorite part... the cosmic horror aspect. I would have been fine with more Prometheus-esque sequels. But like I said, someone will always be unhappy.
How much of Covenant will be Ridley bending his will to the people who said they want more aliens? How much of it will be just the natural progression of the story? It is yet to be seen, but I hope it's at least partially the latter. And while I will never get tired of seeing cool ass xenomorphs, having more Xenos for the sake of having more Xenos is silly. So I hope Covenant still retains some of that cosmic horror aspect. I think it will. From the trailers we can see that we get some exploration of the juggernaut, but I hope there is some new territory as well. But I also know there are more sequels. So if this is Ridley's more action/alien oriented film he had to make in order to tell the story his way later on, that is understandable. It is a business after all, and no money = no movies.
As for the spoilers themselves... I already kind of feel like I know the whole movie lol. I'm not complaining though. I'm a sucker for spoilers. I generally know what I'm getting into when I go see a movie. And having twists for the sake of twists is silly. I think truly great movies have genuine/organic twists/surprises, not forced ones. So spoilers are not a problem for me. But when they're releasing so many spoilers, you have to wonder...
Some people are saying "red herrings". While I'd like to believe that to an extent, because there's something fun about being "tricked" and surprised... I just don't see it happening because some people will see it as being "cheated".
But I think you're right, in that they're just trying to reassure people that this is an alien movie that will actually contain plenty of aliens. All the sequels after the original Alien truly ruined the "less is more" approach. One Alien will never be enough again. I don't want to give the wrong impression though... I love this franchise. I just hold that first movie nearest and dearest to my heart.
My wishful thinking about the spoilers is that the movie is just so chock full of content that they know they can successfully spoil this much while at the same time still deliver some genuine surprises. Overall though, I'm hopeful that the movie will be great and I'm very excited for it.