I choose to be entirely optimistic, and claim that this is now a Luigified(Lucafied?) character.
Luigi/Lucas' fireball/pk fire: Remain horizontal and shoot farther, even while in the air. Little bit less powerful, compared to Mario/Ness', which have shorter range, but possibly do more damage, and in the air are fired downwards. (distance and damage un-confirmed with Ness)
PK Flash and Freeze, although the execution seems to be very similar, have different functions. One freezes, the other blasts the hell out of them. Back to Mario/Luigi and their Up-B. They were executed the same, but one acted as a combo while the other completely useless unless you hit exact from the start, then it was BOOM!
On top of that, I am under the impression of an entirely new standard moveset, and ****it I WANT MY YO-YO!!