"Light" is relative. I have a very light bow I really enjoy and is probably of a bit better quality than yours -- good but no master model, very well made but not a premium piece of wood. Not worth anything, though, as it is too light for most tastes and can't be identified.

Then there's flexibility, which might be more of what you are picking up on. A bow that is too flexible will be less responsive and not function well for fiddling. Classical players tend to like a very strong bow.

If I were you, I have the restoration done and see how you like it then. Have your friend weigh it and give you his flexibility rating. That gives you a point of reference. Then, if you don't like the bow, you can try out others with that in mind. Most sellers of bows will allow you to do a test run.