Flight, invisibility, super-speed...these are cool things. The powers listed below are not:
Zan (of The Wonder Twins)
Ok, so the sister can turn into any animal. I can see where this could be cool, and why she and Beast Boy have never hooked up is beyond me. But the brother...he got shafted in the powers department. When they do the terrorist bump, Jayna turns into an eagle and flies off, while Zan screams "Shape of...water!" like that's something cool. Next, it's into the bucket so the blue monkey can carry him to the mission.
With a super power like that, he might have come off better just losing the costume and getting a job as a lifeguard at a public pool or something.
Ashley Crawford is a supermodel with a great figure. When she decides it's time to fight crime, she turns into a female version of the Blob.
Most superheroes do all they can to stay in shape, while Bertha does all she can to stay out of shape. An active member of the Great Lakes Avengers (now the Great Lakes Champions) since their inception, it's never really been clear what the advantage is of having a really fat lady on the team.
Listen, I love the characters of Hawk & Dove (the originals, anyway) and really think they have cool costumes and got shafted in a reboot, but Dove's powers just aren't that great. He gets to be stronger and faster than he would be in normal life...but he's a pacifist and doesn't fight! What exactly is the advantage of enhanced speed and strength if you're going to go out of your way to keep from actually hurting anyone?
I know when they were brought into the JLU cartoon series for an episode, they actually made him cool. Still, it was a little like cheating since they gave him super-speed (which he didn't have in the comics) to make him a second-rate Flash character.
Top this all off with the fact that he was named after a bird, but he couldn't even fly! Ok, so in the reboot DC finally caught that little discrepancy and fixed it, but it was too late for Don. If he'd had flight there's a really good chance he'd have made it out of the Crisis on Infinite Earths alive and well!