Gentoo has been investigated:
Gentoo would solve one issue, but generate new issues.
- It’s a rolling distribution. Changing too rapidly. While Whonix was based on testing for a while, many issues were generated from that. Stable distributions are much more usable.
- There are package manager and other security issues with Gentoo’s, see: Issues · Whonix/Gentoo-Port · GitHub
- porting to Gentoo would cost lots of time and effort