I agree with changing things up.

When I first started commuting earlier this year I had a set route and stuck to it. Lately, though, my routes are all over the place, mostly dependent on time. Some mornings are a straight 2.5 miles, others are 10. The ride home tends to see anywhere between 4 and 30 depending on what time I get out of work and how much stress I need to work off before I get home.

Variety is good.