You sound pretty optimistic, man. Realistically, however, there's going to be some lag. No amount of work on an online game can admonish lag simply because connections between users do fluctuate all the time. The only thing that Sakurai could possibly do is tweak the gameplay mechanics in accordance to the lag that may occur. Take Halo 2's auto-aim and the large hitboxes of the Elite/Master Chief toons, for example. As long as you place the reticule over somebody else and you are within range, you're guaranteed to nail them with a bullet---especially one that is potentially fatal. I know that sounds pretty insipid on my part, but it tends to be ridiculous when you get a headshot from a Magnum that was aiming for your sternum (I've tested it out with a buddy of mine before). That was Bungie's answer to lag---a pretty crappy one, in my humble opinion, but an answer nonetheless (though I must say that they have cleaned up some of the stuff in the Halo 3 Beta).
The "n00b" solution was solved rather simply. Friend codes are the order of the day here. I can't really say anything else about that. Sakurai did mention, in passing, that if there was an online component that there would not be a ranking system.
The real question is what kind of tweaks could there be to the core game to make it more palatable to online play? Sakurai and Company have worked on this game for a long time, there's no doubt. However, we only know as much as we have been given so far. Hopefully Sakurai and Company'll shed some light on this mystery in the future.
Smooth Criminal