Google Maps is ok, but not the best for bike routes. Since you're biking to work, does anyone else there bike in? Or at least anyone that has/used to? I had a pretty good route to work, it was what google recommended, and I had no complaints, but talking to another guy about his route, I gave it a try and it's way better. It's about .05 miles (not .5) longer, which is why google didn't give it to me.
Baring that, I agree with just exploring. Crossing tracks or a river is tricky, limited options without going way out of your way. So just have to find the best route that minimizes time on a crappy bridge.