This. As long as they don't contradict each other, no need for references, focus on the story at hand.
They are definitely trying out a bunch of different "old" and "new" ideas now, and I'm glad we're getting this mix.
I for one am conflicted on the design of the marines. On the one hand, I love the original look, but on the other, it's so outdated. I think what Tristan did in Defiance and on this cover is great, of course. If a setting is chronologically close to Aliens, than keep the original armor, or just have a slightly different version. But anything that's further in the future, some variation on the familiar design, keeping the same core features while adding onto it, would be nice. I personally really liked what AVP2010 tried to do in that regard.
On the other hand, in this EU, we can always say - budget. There's a lot of marines, a lot a space to cover, so some, or most, get the cheap stuff. It works. but not the best you can get. Maybe introducing some elite squads could leave the door open for new armor and weapons.