I actually love riding a MC in the city, especially Los Angeles and in Europe because of lane-splitting. I'm actually more wary of riding up here in rural Wisconsin because of the deer everywhere.
Motorcycles are great and one of life's great pleasures, IMO but there are things you absolutely MUST know in order to stay alive and in one piece. Some of it is just common sense like defensive driving and situational awareness, etc., but some of it is more esoteric and learned over years of riding. I wish that I could come out there and instruct you, I'd gladly do it if we were in the same locale.
I ride as though I am an invisible ninja just slicing through traffic and no one can see me. Everyone is going to do whatever they are going to do as if I'm not there. If they are thinking about turning left, they are going to turn left. Same w changing lanes, etc.
You have to learn to read people's "body language" when they are driving and anticipate what they are about to do. Most of it is predictable, fortunately. It can be very zen because it requires focus and complete attention.
A good BMW airhead, almost any model, is a great city bike. Big improvements happened in 1981, that is the oldest year you want unless you find a great /6 from mid-'70s. R65 bikes before '81 are to be avoided, I had a '79 at one point.