I just beat the game the other day and would agree with the three star review. The best thing about the game is the presentation and makes the frustrating portions a little easier to swallow. The thing is, I really want to see more of this world and what it has to offer. So what should a sequel have?

I would actually do two games, Mirror's Edge: Blue and Mirror's Edge 2.

Mirror's Edge: Blue
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DLC episodic game to be later released as a retail product with Mirror's Edge.

The game would focus on the police force in the game and how they deal with this world. Would play a detective who knows Kate, Faith's sister, and the fallout of the events of the first game directly after the ending.

Would continue the first person perspective but more focused on gunplay including new weapons.

New gameplay elements including some sort of cop "instinct" instead of runner's vision. You will see things turn blue if you have a feeling about something that is about to happen or where to go.

Would lead into the story of Mirror's Edge 2.

Mirror's Edge 2
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Multiplayer modes including Tag, Runners vs. Blues, Co-Op, Free Running (similar to skateboarding games).

Full 3D cut scenes, either real time or rendered. No more 2D.

Visually seeing Faith more during the story.

New co-op only moves.

Create a level: Allows you to place buildings and structures with time trial goals.

I agree with changing the cutscenes and creating your own levels sounds like a really good idea.  I think the next game should be longer and there should be a lot less combat. 

an apology

"an apology"

Hmm, for the next game, I want to see some "messenger" missions, afterall, isnt that what Faith acutally does? And a lot less combat, and NO GUNS!