You also left out 'Johnny Williams' a one time holder of the British and European Heavyweight Titles :-)

He also won the gold at Super Heavyweight four years later, also for Canada

This is a no-brainer. The answer is Lennox Lewis. Easily.

I agree Lewis hands down

Well for one Lewis beat Bruno, so that pretty much makes him a car with no engine. Lewis was an amazing fighter, who had a powerful punch and skills to back him up.