Most of the character problems are directly the result of kids show
Sabine not getting killed by Vader(in that cool sudden way)
Ezra not joining the dark side(thus making his character interesting).
Ezra was screwed either way. If goes dark, he’s too much like Anakin, but if he stays with the light, he’s too much like Luke. Honestly, he’s just a very bland character. Turning him to the dark side wouldn’t change that. He might have been a bit more memorable if they’d made him an alien like Ahsoka, but they couldn’t even do that. Of course, it wouldn’t fix the problem, but it would have been nice.