Sorry, but I don't have much experience with porcupuffer, but I remember Lakitu sucking so bad in every game they appeared in.
You're right, but the only experience so far in that game with Porcupuffer is in my extremely hard level The Rat Race Run.
Lakitu isn't so bad in Yoshi's Island, I like messing with Wall Lakitus there, though Wall Lakitus can go to hell in Touch & Go.
Oh they appear. Some of them throw spinys at you, some them poke out of walls, some of them try to snatch Baby Mario away. But they're easily deal with thanks to Yoshi's long tongue and throwing eggs at them.