I went to school for Esthetics before going back for my Cosmetology education. At the time, like you, I was thinking about dermatology. But, I know that I would not enjoy being a doctor and dealing with skin issues that way. I prefer helping people by showing them how to use cosmetics and experiment with their features -- hair and makeup. I found that esthetics work wasn't fulfilling me creatively, enough, so I went back for hair. But, being an esthetician will allow you to help people in the same way (maybe even better) that the derm can. Dermatologists will tell you that they deal with what lies beneath your skin. They get to the source. But, as an esthetician, you will be able to help your clients pursue beautiful skin on the surface. You help clients maintain good skin, teaching them what you know! (That was always fun for me.) Working in a dermatologist's office may be better, too, if you're interested more in the medical side of it (opposed to the artistic side.)
The nice thing about going to school for Cosmetology, compared to Esthetics only, is that you're exposed to a lot more. For example, hair color will definitely help you when it comes to your makeup. The color wheel is the same, but you'll get experience in mixing and testing formulas when dealing with hair. Also, I was big on Art in high school. Basically, any type of education or recreation that allows you to PLAY with color and exercise your talent (in a non-restricting way) is excellent!
