Hey, Kathleen - great post!
I have wondered myself whether this interest in appearance betrays a certain shallowness, but have made some level of peace with it by paying attention to how it makes me feel when I'm satisfied with how I look.
Basically, when I'm confident about what I'm wearing, I can then forget about it and focus on issues of greater consequence. When I have thrown on something that I think is frumpy (or, just as bad but more rare, too "flashy") it distracts me all day.
Pay attention in the morning, then forget it all day. Seems like a good tradeoff to me!