I usually use bananas as part of my approach, although it's possible to get a throw in if your opponent trips or uses his or her shield, but the dash attack U-Tilt/Smash usually hits or pushes them back enough that they can't shield grab you. Otherwise I use N-Air for a vertical launch and sometimes B-air for knock back. F-Air is a bit risky, although it's out longer and has a better reach, it has a quite long recovery, especially when it hits the ground. Mix 'em up a bit,so it's harder to guess. Try some improv, like running through your opponent who might think it's a dash attack, and hit an unexpected F-Smash. Don't know if that works, but that could (or not be) a WTF moment if it works.