Let's see:
Downsmash is a great everything punisher. If the spotdodge, they will get hit by one of the later hits of it. If they roll towards/past you it also works well.
Forward Smash is good for punishing people who roll away from directly in front of you.
Charged needles are also great for punishing people rolling away.
Chain-Dragging is GREAT against people who sidestep in front of you. If you get them thinking you're going to running grab them, and instead throw out the chain and drag it, they will sidestep and eat a ton of damage. Also works if they shield, since this thing pokes like crazy. If they roll behind you and you predict this, you can throw out the chain in the opposite direction, or alternately just reverse-Drag it to drag them in front of you and rack up even more damage. Work on your chain Dragging, it's a great defense-punisher move.
Uptilt is decent, due to its range and duration, if they roll towards you or sidestep when you're right on top of then.
As for airdodges, the Nair is great at catching them out of it, as it lasts longer than one.