I think without Eric, the game would be just like the many other incest games and boring. The fact that everyone hates him so much means that he's working as intended. There is a lot of drive to progress with all the girls, due to trying to outdo Eric, and not let him get the girls.
Pretty much this. Eric is what makes Big Brother, well.... Big Brother. That's not to say that DS took all the right decisions in character build-up, but his inclusion in the game is what pretty much drives the whole story.
Also, it's hard to fully please 100 people, let alone 2,000. Any, and I do mean any decision a developer makes, down to the font color, is to bound rub some people the wrong way.
Having a select few trampling the comments with constant rambling (like Phantomwhatshisname) doesn't really mean a decision/idea is inherently right or wrong.
(And if people are willing to continue paying for something that is so very much not to their liking, well, joke's on them).