Not really. Though MK, Marth, Wario and Jigglypuff are some characters that make the best use of short hopping. Mostly it takes away Olimars grab and since his air game is somewhat lacking, its hard to counter.
Nair or Utilt would work if timed correctly, but it kinda has to be perfect. If the player sees it coming they can fall away from the attack and hit you.
You forgot to mention Olimar in that list. Try sh to nair, it outprioritizes and cancels alot fo moves, and has so many hits that it punishes most people who planned on shield grabbing or air dodging. Also, f'air with a yellow pikmin has a ghost hitbox that extends your reach by a sliver. That sliver is enough to catch some shoppers prematurely. Spot dodge to jab also works for knocking your opponent away real fast. And if they DI back: fsmash.
These, however, will not work against MK or Marth most of the time, and that is when grabs really play a big role. Olimar's grabs are beastly, the only advantage that he has over some characters. Remember, the pikmin Oli sends out grab on the way out
and the way back, meaning that any spot dodgers hanging out close enough to olimar have to deal with a return trip, which is very difficult to time and, if dodged properly, completely immobilizes the player. Shield and grab, my friend, sheild and grab.
And if all else fails, whistle ftw.
Umm, olimar can't grab people in the air. Some characters can, but I believe olimar can't. And a short hopping Olimar might be interesting, but against floaty characters, I would rather be on the ground. Sh to nair might work against Wario, I'll have to try it. But against MK or Marth, i'm keeping my distance.
Olimar can grab people in the air, actually. The timing is difficult, but it can be done.