No, that may be a good (natural) weight for you.
The greatest all around fighter in the history of boxing was Sugar Ray Robinson according to near all boxing expects. And Sugar Ray was six feet tall (or 5' 11" some say), and his weight varies between 150-160 pounds during his professional boxing career and he was a great champion. You are very, very close to be the exact over all height and weight as the great and legendary Sugar Ray Robinson.
Sugar Ray could do it all. He could box. He could punch, and also had super defensive boxing skills also, as well as other amazing boxing skills. He could even knock you out going backwards in the ring. In his early professional boxing career in the early 1940s he killed an opponent in the ring with one punch a left hook.
Fairly fit because of squash, football and rugby which I play alot.
Sounds like your already in pretty good shape getting started in taking up boxing. That's good, that will get you a head start in getting into shape for boxing.
Also how would I go about improving footwork?
Cause I know for a fact it really won't be up to much.
Nobody's is when they first take up boxing. There are several things that you can do to improve your footwork for boxing. But the best thing that you can do to improve your foot work is to skip rope.
Skipping rope will also build stamina, and strengthen your legs and ankles as well as to improve your foot work too.
Nothing will improve your foot work more than skipping rope. But you got to learn how to skip rope. Never stand in one place when you skip rope, more you feet around. When you skip rope step from side to side and step forwards, then backwards and stepping side to side move your feet around. Never skip rope standing always in one place when you skip rope for it's bad for your heart to stand in just one place when you skip rope. It's great exercise. You'll get better at it with practice.