personally, with something like this, I'd love to see some actual script goodies. I would really love to see something like the Aliens movies, as well as, to a lesser extent, other adaptions of the Aliens universe.
Take these for example.
This article features the AvP2 Marine Weapons that you were able to use throughout the marine campaign in 2001's Aliens vs Predator 2 game for PC.
www.avpgalaxy.net
flamethrowers are a must, shotguns, smart guns, I think the welding torch would be great. I think this would be one example that, to have and include scripts that match the environment would be crucial to benefit the setting.
that's just me. I would also like to see some variety for the xenos faction, below and attached is a table of how aliens on the SS13 server Colonial Marines. it's very intuitive, very action packed and racks up on average 130 players daily, the height I personally saw was 156 players. Right now, at the time of posting, it has 112 players. So, it's very action-packed and keeps people involved. If you'd like, I can give more advisement on how the Marines operates in regards to the aliens and xenos, because I think it's very amazing.
I don't think that we should be taking their ideas, but more use this as inspiration for our own, independent flow on the server.
Now, in regards to the general story of Aliens, I think that we should be okay getting killed much more often than other roleplays. This is a very dangerous world that we live in now where our players would be pitted against the pinnacle predator of evolution. I'd love to see also some settings and plot-points from Alien: Isolation and other games to facilitate this, that just one of these things can wipe out a lot of people. A whole nest of them wiped out an entire colony with only one survivor of the initial colony and 2 human survivors (Hicks and Ripley) for the investigative teams that followed.
I also think that anything beyond Aliens (Sequel) should be invalidated from canon. No Alien 3, no Insurrection.
Maybe Prometheus, but that story was really inane.
I would even consider throwing out an event prior to the aliens mission to give people action, let it be their first "combat drop" followed by the next mission being the real deal. In Aliens, they go as far to discuss the "Bug chase" or whatever the Marines said in the movie, implying that they've met unintelligent life before that was hostile to humans and they just killed them. Could do something like that?