Mostly, yes.

I always struggled to find time to exercise and stay health. then I realized that time spent in car is wasted time. might as well make it exercise instead. from there, I learned to love bike commuting, since about 2005, have made it a regular part of my life.

Helmet.

Fresh air.

"Instead of showing up to work frustrated with traffic, you can show up relaxed, rejuvenated, and ready to face the day." 

Rain/getting soaked.

Awesome views of mountains.

Always buy wrinkle-free clothes. shirts and pants. lots of options to change at work and look professional these days. even "business casual" gives you lots of freedom to find something that works for you.

For me, because I have a longer ride, the key is finding a place to shower and safe place to store my bike. luckily, my office has both.

Yes, a couple that left marks.

(1) while crossing a merge lane, I hit a rock in the middle of the road. completely lost control and flew over my handlebars. wrecked my helmet (thankfully it worked) and my jacket. bike was OK except for some scrapes. luckily someone stopped and helped me get sorted. was a bit shaken up but otherwise alright.

(2) the last part of my commute is downhill and there are lots of roundabouts. pro tip: in fall when wet leaves on the ground, take the roundabouts slow. took one at full speed and ended up on my ass a block down the hill.

It is a law to wear a helmet where I live. I think it should be a choice, not a law. I think if we had proper infrastructure (like protected bike lanes), then helmets are unnecessary. However, as my commute does include a couple stretches sharing busy roads with cars, I do wear a helmet when I commute.

Yes. I now work from home majority of the time. my commute now is to drop the kids at school and/or to the pub to meet friends for a drink.