Okay, The meat of the Idea I'm working with is that the Ark is not used anywhere near as much as in the original film, only as a last resort as the Demons flee to EARTH and the Marines have no choice but to follow.

I don't really like the idea of them using alien tech that they can barely control or understand, so instead they use their own tech that they can barely control or understand.

We see that it is a dangerous and unpredictable process - after what happened to Pinky. So the core of my idea in this area is twofold -

A The Ark only becomes a focal point later in the story [Sam's opening monologue will be dumped most likely]

B It's supposed to be a futuristic movie...Where are the spaceships?!

The Marines will not get about on a freaking spaceship, specifically this one...

Now, The first thing to deal with is the fact that they travel to MARS via the Ark from EARTH. Here's the head scratching part, I'm looking at attempting to splice shots from the arrival at BOTH of the Ark rooms.

We see the elevator doors open and the Marines step out into a foyer and meet UAC's PR rep. This was an EARTH scene, it will now be implied that we are already on MARS - Having our ship already docked / landed.

The PR guy warns them not to get to the Ark or they may get sucked in, I'm planning to add some VFX to imply the ark here isn't operating at peak performance... The kid will ask if it's always that rough and Pinky will roll forward and explain just how rough it can be.

Now there's a LOT more to it than that, but there's the basic gist of it - I'm ironing out a lot of plot points to make this idea work out.