Commuting daily with an Expensive Bike, tips?
I think that picking up a second bike is definitely a good approach. Not only does it allow you to not risk your more expensive bike getting stolen, but it allows you to  have a bike more suitable to commuting. You can put fenders and racks on your commuting bike.  Perhaps wider tires if you want something a little more comfortable.  Since you are good with a single speed, this can also be very advantageous on a commuting bike because they are extremely reliable as there are much fewer parts that can have something go wrong with them.