It depends really.
I've changed my playbys from a lot of sources in the past. Arali'an's now fits her perfectly when it didn't before and I went through a few faces for her. Same with Tatiana, too. I'm happy with them both. Daron's (if he was still alive) probably would have had to have changed because he would have been older and race wise? He would be dead.
Sometimes I watch a tv show and get an idea for a character or I have an idea then see someone, and instantly think. PERFECT! 😄
So many options!
Most of us (or probably just me) pinch their character's faces from an established tv show, movie or favourite celebrity.
My characters have been around for a few years now and I've found my sources to be a weird mixed bag - from terrible movies to J-rock (yeah I went through the phase, no I'm not ashamed 😉)
My question to you is, where do you get your faces from? What makes you decide that the mug you're staring at is indeed the right fit for your character?
Or are you the type to see a face and want to build a character based on it? (I'm guilty of this too 🙂)