I've had a motorcycle as my primary transportation since I was a teenager (nearly 50 now). It's cheap, and if your SO has a car and you don't live in a cold area that freezes often, easy to work around the limitations. I don't mind the rain or cold, but ice will kill you instantly.

Also, I like the classic old bikes from the late '70s and early '80s, which are easy to work on and have large online communities that can help you do pretty much anything. You can also get great ones for $1K - 2K. But those come at the expense of reliability, so it's helpful to either have more than one, or just buy something newer and more reliable for commuting.

I think it's a good way to go, but if I had kids, I wouldn't do it. I've only had 2 minor accidents over the years, but one resulted in surgery (knee - no big deal). I consider myself lucky in that regard.