I did pediatric derm and complex adult derm.
The clinical part of derm is really fine, its very efficient and fun because your patients are generally healthy (and even if they're not, you don't deal with the unhealthy part), however the residency is intellectually quite rough, at least from what I saw from attending the resident classes. And from speaking to many residents and even some who have completed residencies in other specialties before entering derm, it's one of the hardest board exams. I'm just not interested in the grind anymore, I want to start prioritizing other aspects of my life, so I'm going for family. The flexibility of family is also really nice, you can kinda change patient population during your practice by "specializing" in certain types of practice.
It's super interesting though.