Update:

so for the past 25 work days, I've been able to do:

18 bike and/or bike on train
1 train/bus/walk (no bike - heavy rain)
6 driving

so, down to 24% driving and 76% biking/transit. Bike-on-train is definitely my new default, and I'm having a blast.

I called my car insurance and they dropped my rate by $400 / year. That just paid for my folding bike with an extra $100 to spare, thank you very much.