That clip looks great! So you want that one polished and start a new lip sync piece. I like that plan!
Regarding the fighting clip, have you done any camera work in the past? I think this shot could benefit from it. Right now the frame is very bottom heavy and feels like you need to tilt the camera down, up until the ninja jumps up at the end. Are you comfortable with camera work or would you prefer to leave it like that?
Anim wise both characters are in a really good spot, nice work! I would suggest to start offsetting the action a bit more. Right now it has a bit of a pose-to-pose feel to it, right off the bat, when the red guy puts his arms out at x15.
Also, watch out for twinned poses, like the ninja's arms from the beginning on until x38. The ninja also slides to his new position on x47. It doesn't feel like he's shifting the weight properly and taking the proper steps. I would take a lot a that section again.
Watch out for a clear silhouette and avoid tangents, like on x42 to 49, where the ninja head looks glued to the red guy's knee. Keep the negative space clear and clean.
How the ninja moves back from x49 to 53 also feels a bit too pose to pose. It's as if the whole body moves back, using all the body controller's rotation channels at the same time. Think about how the movement can be lead by the head, then followed by the chest and finished with the root. That backwards move also ends on x56, where the ninja is totally off balance, yet he just moves the body forward and takes a step back to x59. On that frame he still feels a bit off balance, but the momentum of swinging your body back so quickly would not just be gone so quickly. I would move the ninja's left leg further back to really stop that backwards momentum.
So overall, think of the movements in terms of what body part initiates and leads it, what is the force behind it and what kind of momentum comes out of each move. What does the body have to do to stop or counter that momentum and what is the proper weight shift and timing during those moments.
You're in a good spot, now it's time to polish it, just like you said. :)
Hope this helps!