shapular
Smash Ace
I think the well-designed characters are the ones who rely more on fundamentals than gimmicks. For example, Mario, Marth, ROB, or Charizard. Most of the characters who are basically ported from Melee/Brawl are this way. Poorly-designed characters rely a lot on a few specific unbalanced moves or other gimmicks to win and don't necessarily need good fundamentals. Mewtwo is a good example of this, and doesn't really need any explanation. Ivysaur is somewhat this way since he has some free setups into Vine Whip, which has a ridiculously huge hitbox and is as strong as most smash attacks, and is the only character who can force you to approach without actually threatening you (by healing with neutral B). Snake relies heavily on the dumb side B to sticky to back throw(?) to detonate C4 combo, and doesn't have a lot else. Zelda's Din's Fire is basically a weaker Snake C4 that you can put anywhere and can't hurt her, and Nayru's Love is a better spotdodge/airdodge. Otherwise, she's fine. Characters that don't feel like they belong in a Smash game are also poorly-designed. The obvious example is Lucario, but Lucas is like this too. The other characters I think are poorly-designed are Wolf, who was meant to be a slow space animal but turned into a faster space animal, and Toon Link, who was re-cloned into Young Link for no reason even when Toon Link was already a very good character in Brawl.
Note that well-designed and poorly-designed don't necessarily imply a particular tier position.
Note that well-designed and poorly-designed don't necessarily imply a particular tier position.