First of all, Lucas clearly has the better recovery. It goes farther, and he has his rope snake to help, too. Ness makes up for this in other ways, however--his second jump is larger, for starters.Can someone tell us about Ness' recovery in general? Is it worse or better than Lucas?
Lucas has a tether recovery, but infortunately I heard that because of edge hogging, it totally destroys characters who rely on tether recovery like Capt Olimar, but Lucas less so because he can do a PK Lightning recovery.
Does Ness have a good recovery you say? Because it's harder to have Ness hit himself with his PK lightning, I hope they balanaced it by giving Ness like two jumps instead of one or something.
As to the aiming, I'm pretty sure the two aim exactly the same in most cases. I've played them quite a lot, so if I'm compensating for differences in aiming, it's a subconscious thing. Oh, and as far as aiming from Melee to Brawl, it came very naturally. You learn the motion in no time flat (I managed to aim pretty much as I wanted to from the start with Lucas, and it took just a tiny bit longer with Ness).
Ness's is wide but fast, Lucas's is slow but narrow. All in all, if you aim the same, they get to the same point at the same time for most angles. Think of a turntable or record with two points on it in line with each other. Both of these points would rotate around one complete circle in the same amount of time, but the inner point travels slower because it has a smaller radius and travels less distance. The inner point is the path Lucas's PK Thunder takes, whereas the outer point is Ness. Get it? Ness has a bigger radius but more speed, Lucas has a smaller radius but is slower, but they rotate in the same way and reach the same point (the characters's rears) at the same time. Of course, this is going to be a little bit off in some cases--most notably the downward angles.
Oh, and as to the PK Flash test, I'll do it next time I play. Unfortunately, at this point that's probably not gonna be until Saturday. EDIT: Oh, you mean you want to see if Ness can be interrupted? Yes, he can. There's a slight delay, so probably Ness was hit after he detonated the move but before the explosion came.