The lag might have something to do with the lack of people playong online.
I hardly have noticable lag when I play online and while there is a bit of a button delay that is expected in a ny fighting game where the game delays things so that people are where they are on screen.
I don't get lag very often unless I play on anybody and even then it isn't crippling.
When I play with anybody people who have an orange dot next to their name hardly lag for me either.
I rarely get too much(key words, "too much) lag with "Anyone mode".
I do occasionally get into a match where the lag is horrible, there is delay on the buttons from registering, etc.
What I do is simply leave the game, and look for another game.
I usually find non laggy people to play with this way, it only takes one or two tries to find a game with no lag.
Of course, some games may occasionally have a huge lag spike every 3-4 games that lasts for 10 seconds but afterwards, it doesn't lag anymore.
Speaking of Online, too bad you can't request a friend invite or something over Anyone mode. It's silly that a T rated game(T rated) is limited and "too safe" in online mode.
They should have added chatting and added friends invitation in game, BUT added the option to disable/enable chat and added a disclaimer "Never to give your personal information away".
Edit: I take back what I said about laggyness. I am guessing it's because I mainly play at early morning, past midnight (1-7 AM mainly) is why I rarely find laggers.
So I decided to play this morning(8-11 AM), nothing but laggy games. I occasionally found a non-laggy game, but that didn't last long, it'd soon become really laggy.
3)The CPUs only fight humans and WILL NOT fight unless you are in the middle of the fray. Play a FFA on Smash64. I bet you had fun didn't you? Why? Maybe it's because not only do the CPUs treat you equally as other CPUs they also have the fight much more spread out. For example 2 people could fight on one side of Sector Y and you and another can fight undisturbed by other coms on the other side. In Melee it was like Brawl a little bit, but at least the CPUs fight each other in your absence.
Hmm, in my experience the computers rarely just go for me, and I played a lot of Brawl with computers(before I managed to get Brawl Online).
Although, when they get a Final Smash or something, they almost always target you with their Final Smash.
When there is two computers in range of the Final Smash, they rarely use it, they always wait to use it when I'm in range.