- Haruyuki & Kirito is basically the same type of MC, the most generic.
(In Kirito's case, Heathcliff, then Asuna, give him reason to fight. In Haruyuki's case, it's Kuroyukihime.)
- I would say Kuroyukihime is superior as a character but that won't be true to anime-only watchers. So I'm going to say that they're also basically the same Ojou-sama "dash" heroine, despite having different image.
Here are differences:
- SAO is MC-driven. All the side characters are mostly unimportant after their arc is finished (hell, even Asuna, a main character, has no importance in the last arc.) Accel World is only half as MC-driven as SAO. It's more of the "group journey with one first-person view." (what was the term again? I'm just a watcher.)
- Kirito's personality is superior than Haruyuki. (Kirito is more decisive. That's your type of hero, right, Helix?)
- But that's where Kuroyukihime makes up. The difference lies in the type of relationship between the pairs, which is affected on how large is the scope of the story and where it heads.
Kirito is main while Asuna supports from behind (and they're pretty comfortable with it.) But it makes their relationship rather flat to readers and watchers after the Aincrad Arc ends.
(Lovey dovey is all they got after that, MR explained Asuna herself more than the romance, and whatever romance there in PA in the end it's still pretty lacking.)
Haruyuki prefers being support but Kuroyukihime is the "supporting-leader" type. He wants Haruyuki to take initiative (most of the time, not getting what she wants straight away
) but she knows Haruyuki looks up to him that's why she keeps her leader figure even around him. (It's her way of staying as close as possible to the boy.)
While mostly repetitive throughout the story (and in the end it's as flat as
any other Reki Kawahara's romance stories,) their relationship is always nice to follow.
- Kirito is underdeveloped (not undeveloped. If you follow in order of each story, you'll get it, and that's what the anime of SAO did. They did well as far as 14 episodes, the rest is history
Haruyuki made more development. But because Haruyuki started lower than Kirito, in the end, it doesn't really matter.
- Kuroyukihime is more developed than Asuna (who only has 3 development: after meeting Kirito, after dating Kirito, and one and only Mother Rosario arc which explains her background,) because one of the main driving force of Accel World's main story is Kuroyukihime's past & search for answer (of the true purpose of their world, details closed.)