For me, the Reapers and Darth Vader have met the same fate. By revealing too much about them, or because what was revealed was so rubbish, the characters have become forever damaged.
In the original SW trilogy, we learned that Vader was once a Jedi, he was Luke's father, and then saw his face - one reveal per film, perfectly balanced. Vader's past, what turned him, and his disfigurement when mysteries added to his appeal. Post-prequel Vader became a whiny brat who turned to the dark side because he had some bad dreams: RUINED.
Bioware did the same thing to the Reapers, but somehow managed to ruin them in their first trilogy. ME1 we found out about them, ME2 we got a glimpse at how they are made (or a new generation of them), and then they decided to reveal that they are just synthetic dullards locked in an infinite loop based on an idiotic, tautological fallacy. Yay.