I actually kinda like the lit up boots. It's a small thing, but I feel like it adds a bit of character to the animation without being too distracting.
While I like this, and think it's fairly solid, I think you could definitely make the upper body more expressive while he's charging up. He does a really quick motion with his left arm, but then he just sticks it down by his side and it becomes dead weight, which seems kind of odd to me. I would think if he were gathering energy, he would show it in more ways than just a bright blue ball, maybe by drawing himself in, or shifting a little to the side.
Although, I don't really understand the personality of this character, so that non-telegraphed sort of motion might be appropriate?
Also, I have mixed feelings on the palette change. I feel like the blue on his coat is a bit too saturated, although I like that the purple is pulled out a little bit more. And I'm not sure if it's because of the palette change or if you actually changed the frames, but the blur feels toned down, and the impact looks weaker because of it.
Anyways. I'm pretty new to spriting and animation myself, so take everything I say with a couple grains of salt, but I hope at least some of what I said was helpful!