Same here. I didn't like ALO at all.
CONTAINS SPOILER
Reasons: his egoistic sister, who's extremely annoying, becomes a main protagonist. Leafa, who was also boring, turned out to be her. ALO fights weren't interesting. The "story" in ALO was boring. I didn't like the fairy setting either. The main antagonist turned out to be some weird hentai.
Also, something completely stupid is happening: The father allows that man to marry his daughter who's still 17 [still going to school] and unconscious in hospital. It's also obvious that Asuna didn't love that man. So, which kind of father would do this? Also, if the man would have married her and raped her ingame, what now? Keeping her in the cage in ALO, continuing with her being unconscious, maybe starting to rape her in the hospital? There was also that brainwashing thingy...? Well, he wanted to brainwash Asuna, so that she would love him, I think. But still, this kind of story is so weird.
Seriously. SAO would have been 100 times better if they showed more of the happening in SAO and focused there, ALO shouldn't even exist... but this is my opinion.