Some suggestions from a long time fan, I guess Trespasser was among the few games I didnt return to the store while having a buggy computer that was configured wrong for the AMD k6-2 = crashed alot

0. Better graphics, like tesselation, reflect and refract, Subsurface scattering, HDR just go crazy there!
1. Flesh and bone being torn of the playerbody dripping with blood and guts while a dinosaur eats your carcass.
2. Ability for T-rex to actually hurt you even when you prone, kinda cheap as it was. :p
The bigger carnivores should be able to walk into hangars and smash around some crates hehe.
3. Free-Aim much like the one seen in the mod Infiltration or the way it currently works in trespasser while you hold down left mousebutton and move the mouse around. Perhaps without the need to hold it down? I quite like that way. that is: you move the mouse, it changes the center pivot of the gun until it reaches a certain region that makes the whole viewpoint move.
4. She should hold on to items and weapons better in the new engine but still drop it if you run into something with force and smack the gun into something or if you fall from a great enough height to get hurt but not die. Also the suggestion about two slots for guns and a third for keycards. Sometimes I want to carry two guns and still have the arm free. She could carry shotgun on her back and a pistol at her waist.
5. MOAR PUZZLES!
6. Wii-remote support, this type of game begs for this!
And final most important request: Linux Support, please!

be it native or Winelibs as long as it runs OpenGL and not just Direct 3D. ;P