Got some time to take a closer look. Should say appeared bit confusing.
Here's why.
Frame 1 - pose is very calm, not ready for action at all - meaning you would have to spare some frames to get him in ready to attack position. (loosing some time)
Frames 2-9 - not quite clear what direction sword going - from the right shoulder to the left? In anyway  it is should follow an elipse instead of going down then turn left - very hard to control such a motion in a real life.
I tried from left shoulder to the right, see if it makes more sense.
Frames 10-17 - unclear motion. If it is a combo from his first swing position there is no sense to go back (while it is already there). You could try that with a stick - you'll loose a power of inertion. i think it will work better in two motions. Perhaps it is up to you.
rest of the frames - you don't need that much frames as long as you use speedlines.

Any way - that what i come up with - quite sloppy, but i hope you'll get my point.