Is Sabayon superior to Fiesty for those variables?
Sabayon is a variant of Gentoo, I'm sure those that use Gentoo would say its superior to Fiesty. But the truth is, "Linux is Linux" be it Gentoo Debian, Ubuntu, ext. The biggest differences are in the package manager, some distro's may focus on specialized packages for their OS, but any Linux distro can be setup to do what you want.
My opinion is if you are happy with Fiesty and you can do what you want to do, stay with it. Now if on the other hand you are wanting to learn about other linux distro's setup Sabayon on a separate partition and dual boot.