This sounds like a great idea in theory, and would look awesome is done correctly, but would a first-person shooter game inside a Shivan warship be practicable storywise? We all remember what happened the last time Terran marines tried to storm a Shivan transport back in the Hall Fight cutscene from FS1...
Still, if you had "smart grenades" (a la "Space: Above and Beyond) that have anti-grav motors and chase their targets,
that would be really useful against Shivans, I would think!
And forget about slug-throwing machine guns! If I'm storming
any Shivan ship, I want a beam rifle with me! Put
that and other cool high-powered weapons in the game and it'll be feasibly playable.
Just be careful about trying to infiltrate a Sathanas. Invading a 6 kilometer long juggernaut filled with 30,000 Shivans isn't exactly doable without
lots of marines or a small tactical nuke....
