hey dude you're at a point where you can probably benefit a lot from looking at examples of good sprite animations and just copying their timing and the way they do their archs. There's a gba sonic fighting game (sonic battle?) that has plenty of the good stuff, dunno where you can find I think they have some stuff on the pixeldigest tumblr maybe?
your frames are way way way way too slow. the times were all around 20/100, attack animations should have much faster frames.
also I introduce you to the idea of overshot. in karate and fighting in general they always tell you to punch PAST an object, because that makes the fighter put a lot more power into it, the same prnciple works for an animation! a lot of the appeal of anime is based on that, big anticipation almost no frames actually showing the action and it ends in a really really exagerated final pose (overshot) then it quickly kicks back to a normal version of the movement.
I didnt even have to draw or modify a single thing to do that in this, I just switched the poses from your last frame to your second frame and decreased the exposure of the second one.
