Joetbd, I hadn't played Ninja Gaiden in a while, so I watched this video on youtube.
I'm starting to see exactly what you're talking about. A couple of times, the enemy physically gets between you and the camera. With regards to the camera constantly moving, that's because Ryu is constantly moving, and often at a high speed. His movement speed cannot be considered the problem, however, since it is essential to the emotions that players associate with being a ninja. The main problem that caused you to hate Ninja Gaiden is the fact that the camera is extremely close to the ground. Most game cameras are at least ten (scale) feet off of the ground as if on a crane, but the cameraman in Ninja Gaiden is holding the camera at eye level, which means that when the camera pans, it's a much more drastic movement.
If you mean the main series of Prince of Persia, I agree with you. The combat in the cel-shaded adventure from 2008 was awful, as was much of that game. The main series (timeline?) doesn't have great
combat, but there are no glaring flaws; it's a good place to build upon.