Fair enough. Although controlling PK Thunder hasn't changed, I get what you mean.
I'd honestly advise people to work on aerials and aerial control before getting the pk thunder, but both are really important.
If anything, I think learning to short hop is the most important thing a good Lucas needs to learn. If Lucas can only double jump to get somewhere...he's going to get dominated. And I'd say that's probably the biggest mistake I've seen from a beginning Lucas. Quick double jumps that render him helpless in the air.
I think PK Thunder is the move you need to learn after you feel somewhat competent in brawl. It's the "next level" of Lucas. You become a somewhat decent player, then you learn to use PK Thunder to accent and improve your game.
Sorry Tyr_03, but I really think learning PK Thunder first is a horrible strategy...mainly because beginning players find the trick 'novel' and begin to build a reliance to it. Imagine the beginning player who uses PKT whenever the enemy is at a distance, and Up Smash whenever the enemy is next to them. He'll get dominated...
I think using PKT too much (without experience) affects gameplay negatively. It's better to make sure the player can handle themselves without using PKT at all. Only when they're a good Lucas without the move, will they become even more threatening when they use it =)