I actually would like to see the "romance" be fleshed out into the main plot more thoroughly. As a part time videographer and enthused film maker, I can think of many reason's why this would work. I'm no writer (bioware has a team for this), but hear me out.
Any kind of dramatic story requires 3 basic elements. A world, character, and problem. In this case, we'll state the obvious.
World (setting) - Inevitable invasion/attack of the Reaper fleet
Character(s) - Shepard and Tali (obviously more, but for the sake of this scenario)
Problem - Shepards responsibility for saving humanity from the impending doom of all civilized space species.
What can be done to further the grip of the story? By mixing in the romance subplot into the "problem". How they would do this, is up to them, if they could find out how to creatively and effectively implement something like this - the trilogy would be just THAT more satisfying I think.
If they can do this, to make atleast, the story reflect your romance (with Tali, or whoever else) as part of the story line, instead of a side tracked bonus to the game, would be awesome. I'd write more on this subject, as I think it would really help the story of the game, but I'm off of work in 5 minutes, so maybe later