Looks like we have a hint at the next patch.

SAO does everything the dotHACK series did, and improves; if there was any flaw, the "first" season (The World) was rushed and condensed;
we could have seen more character development and less 'harem' tease. and the part 2, (Elf Land) was better (rushed for a purpose/time limit restriction).
i really think people hate SAO more because it went mainstream so quickly, and of course, everything mainstream is bad.

 Open for reaction

No, SAO isn't hated for something as simple as being mainstream. It is disliked for having flat and shallow characters along with one of the more gary stu main characters.
And because i can't be bothered to write something long and elaborate, here: http://pastebin.com/pVhQrd6Y
And if i hated SAO for being mainstream why the pineapple are almost all my favourite manga and anime also things that are mainstream? Doesn't seem to add up buddy, using "hurr you only dislike it because it's mainstream" is an awful cop-out excuse.

Also, truly exclusive content in maple is very rare. For the most part contet ends up being shared between other versions of the game.