[quote=Zherdee]
So we will be only secondary, while Shepard will do all that memorable stuff?
[/quote]

I'm seeing the crew doing big things, just not the pivotal Mass Effect 3 storyline-related things (like killing Kai Leng, evacuating the Krogan female, etc).

The Unity will be evacuating colonists (and holding off the Reapers while they do so), offering assistance to pinned-down squadrons, delivering important intel, emergency medical transport, etc. They'll be doing important things but they won't be making forging alliances between the species like Shepard was.

Also, we won't be choosing which color to shoot in the end, heh.