Man, you pedal fast Jon! ;)
I am so jealous of your commute. Trees, water in the rivers...
And surprisingly, no other bike traffic! I hope you make all of your coworkers and neighbors watch, so they can see what they're missing every morning.
And Ecrew- How professional is professional? Suit and tie? You can always leave some suit jackets at the office. Your pants and shirt won't get too wrinkly in a backpack for such a short time, and in any case that will be covered by the jacket. And your lunch will be safe in some hard plastic containers at the bottom of your pack.
When I bike in, I allow about 20 minutes before I'm expected to be on the floor to just sit in my office in my underroos and cool off before I put on my work clothes. There's a shower in the basement, but I'm scared of it.