I agree, BioWare is always in a no-win situation when it comes to their games. People will complain that their characters don't represent them or that the content relating to all the different possible romances is weak compared to when there was only one option. If they then did dedicate half the game to romances you would have the people that have no interest in them upset because the game is no longer catering to them and has become a "dating simulator" and its mandatory.
This. This. This.
Where do Bioware draw the line on romances? Do you include romances where the LI breaks up with you for some real life reason? (Not interested, moving away, etc). If you restrict romances to certain races and you have X amount of races, who can date who and how much effort goes in? Do they let you choose where to go on a date, then cater for each way that date can go wrong? Do you break up on that date because you wouldn't share your Varren burger?
I'll concede that there are aspects they can improve in, small wins they can make to really improve the quality and experience. But if a LI is meant to compliment the game (Not turn it into a dating sim) then there are going to be a lot of limits, and people aren't going to like it.
Each person has their own dating experiences, these can't all be integrated into the game, the only choice Bioware have is to try their best to make a "themed romance" for each LI. Which they seemed to do. Eg. Tali was good for the typical innocent romance, where as Miranda was the self concious but confident romance. They covered a variety of LI themes and personalities and also catered reasonably well for people with different sexual preferences.
Each person has their idea of what it will take to satisfy them for an LI and I can appreciate the problem faced by Bioware of how do you address as many as possible in one go. Unfortunately I think they're going to cop a fair bit of flak no matter what they do and I really hope it doesn't put them off continuing LI's in the future.