this is super cool! I think with the rasengan thing the colors can be pushed, along with a glow. And for a more action pose you can tilt the character a bit. moving the eyes to focus on the center might also give it more movement to say. (also great hand) And for the rasengan I think having the outside not be fully circle would help it to. For the inside I would also do kinda a vortex spiral kinda thing. Adding variation between the colors is also good. And form looking at a reference it has a lighter lined glow around it. And a really bright center. Usually for something like this you would have a bright center and outside ring to make it kinda glow. Wavy lines around it can also give it more of a power shape. Im not great with effects but hopfully something of this is helpful. Keep it up tho this is awesome <3 | Artwod Feedback