In regards to permadeath, I find there's pros and cons to both sides of the argument. With permadeath, our characters would be considerably more cautious about a number of things. It raises the possibility of player killing which, although SAO doesn't touch upon it a lot, would have to be met with harsh justice which would be interesting to see playing it. Y'know, gritty and shit.
Non permadeath, on the other hand, makes death a bad idea but not an irreversible one. It has some meaning in that you could be watching your friends slowly slip further and further away from reality. It's a bit more intelligent and long-lasting but it obviously wouldn't carry such an emotional punch; a la Moonlit Black Cats.
Ultimately, however, as Jabber mentioned, we're having more of a focus on Log Horizon than SAO. Plus it could be said that unlike the creator showing up in Ep1 of SAO and telling them that if they die in the game, they die in real life, the Dark Lord did not mention death at all. I reckon we're going for non-permadeath then.
Alsssooooo, if we're talking about a lack of roles, I think there definitely could be a debate raised for having 2 characters max per person.