I think there should have been at least a possibility of a full-out happy ending. There was so much sadness and loss throughout the series (especially in the third game), that even with a full happy ending, the ending would've been bittersweet.
Another thing, why is it that a game all about making choices never seems to show you the consequences of your choice. The endings should be based off of everything you've done, not a last minute decision that overrides everything.
Komania's comments