I don't think the tone or atmosphere of Covenant is that different up until the slasher part in act three. The Covenant crew stumble upon the Planet by accident. You have people going down to scope out a planet with some staying behind, a crew investigating a Jockey ship, groups split up, people getting infected by black goo things, people getting killed due to black goo things, David double crossing humans, a female lead character that ends up saving the day.
I guess imagine when they go back to the pyramid in Prometheus, it's not the Jockey they wake up, but an Alien. Then the movies probably play out in similar ways outside of the creation themes in Prometheus.
Really covenant should have played out like it does, but when Davids lab comes up (which is a cool scene I agree), it still continues onto weird Alien like stuff (like maybe a slightly different version of the Neo) then at the end David chokes up the Facehuggers and we are all like " ah ha" the Alien will be in the next one.
I mean we don't even need a film after Covenant, it's done. People only want another film to see David and to see the original Alien, but honestly it's probably just more of the same stuff. David made the Alien - then the Alien killed a bunch of people, then David dies - not even sure if you need to tie in the old derelict either. You can just leave ambiguous.
The end of episode 3 should have been the Alien. I'm perfectly fine with David floating off into space and that's the end because I mean whats left to know? The Alien comes from black goo that the Engineers made.
I'd rather a reboot now or a sequel in a different timeline.