I run Gentoo as my main distro, and have for a couple years now. It’s a pretty stable rolling release (IMO more stable than Arch), and since you’re already an advanced user, the experience should be pretty rewarding!
The wiki is great, and the installation handbook is top notch.
You get to control exactly what features each package is compiled with, so no bloat at all.
KDE 6 just landed too!
But you couldn’t release your own projects based on this under pure MIT or Apache-2.0. Presumably you’d need to include the same restriction about selling on Atlassian’s marketplace.