I mean it's a general interaction design principle. Provide sane defaults, offer customization. As a corollary, if you need to prompt for data, think long and hard about whether you actually need that data.
Hrm, thinking about it, it'd probably also be neat if it tracked what colours users who do choose pick, and then use that information to deduce their favorites. If any of those are available, it should pick them automatically. Even if I went out of my way to pick orange every time, it'd be nice if the app remembered that and picked orange for me, thus eliminating a step.
It may be worth displaying available colors as smaller squares next to the button like this:
┏━━━━━━━━━━━┳━┳━┳━┓
┃ primary ┣━╋━╋━┫
┗━━━━━━━━━━━┻━┻━┻━┛
So that I can know at a glance whether or not my favourite colour is available.
