well, you could contact the management at the depot, outlining everything that happened. Mind you, I'm not sure you would get any satisfaction.
By rights, the driver should not be stopping at undesignated stops and can be disciplined for doing this. I've encountered many abusive bus drivers, its particulalrly bad in London.
My ex boyfriend is a driver for Arriva in London and they get complaints everyday. He has told me, the station supervisors and managers would sit in the office together, reading complaints and howling with laughter. They would then send a standard letter of apology to the complainant.
I think being a bus driver these days, (now conductors are no longer available,) is very stressful. They experience abuse, threats of violence and actual violence on a daily basis, so maybe the day you encountered him, he was on the edge. That being said, his behaviour was unprofessional and over the top and and showed the company he works for, in a negative light.