As the writer, I'm basically setting the tone of the game. In that regard, what I'm most interested in seeing is that in both gameplay and visuals, that tone is kept. What does that mean in particular?
1. The setting is realistic, so the player character should have a (video-game level of) human strength - in this case, a woman's with the training regimen of Lara Croft
2. The visuals shouldn't be overly colorful and saturated in unnatural tones (though purple explosions and blue discharge from alien stuff is fine)
3. The gameplay, particularly player abilities, should reflect this level of realism - no falling 30m and being fine, jumping 10m and running at superhuman speeds like it's nothing
On that last point, the player character also isn't a tank. She doesn't wear a Spartan suit, and even those will die when getting shot in the face with a rocket. The player character shouldn't be able to regenerate health from heavy wounds before getting her alien arm - which will aid in healing - which in turn means that the gameplay should make that clear to the player in the first part.
Lastly: I know there's the option of pulling enemies in with the hook and using it to clear space, but let's keep it mostly realistic - Tamara needs something to anchor herself with if she wants to pull an enemy in, because she's most likely lighter than the aliens in their full suits. Good thing that anchor can be provided by trees, pipes in the walls or other objects that are fixed in the environment. This is just a nitpick, but I think it aids greatly in the sense of realism.
I want the motions in the game to feel natural, have a certain flow to them. There should be no choppy feel to them. The animations must be fluid and pleasant to look at
As project manager, it has been my duty to ask 150% of the work everyone puts into the project. But as a programmer, it is my duty to make sure everything feels smooth. Focused mostly on combad and exploring mechanics so the player can thruly enjoy what planet Gloria can provide.