I'm happy that Trisquel 8 is finally being developed, but I won't have time to help. I wish everyone good luck :D

What do you mean with (open-source) 0_o ?
Maybe Free Software?

I'm curious why you use "Mint"?
I've been thinking around what GNU/Linux distribution should use instead of GNU/Linux-libre because of firmware problem and I was found that "Fedora" is the best choice. According to FSF: https://www.gnu.org/distros/common-distros.html , Fedora "Unfortunately, the decision to allow that firmware in the policy keeps Fedora from meeting the free system distribution guidelines.".

Except these firmwares, Fedora is Free software distribution.

Debian was not so good enough for me because of Emacs's documents excluded in the main repository. And if you included non-free repository for sake of using non-free firmware, you will face an awkward situation that non-free software is around you with ready to install. Anyway, if you want to use Debian in minimal non-free firmware as need only, you might be do it manually which was described in the Debian documentation/wiki and you can install Emacs form source in order to get Emacs documentation.

For me, I've use non-free Laptop that was HPG32 with Fedora and Fully free Lenovo Laptop X200 with Libreboot and Trisquel 8 alpha and happy with both.

I've been using Trisquel 8 for weeks. It's basically ready with just a few things to wrap up. However, if you are unwilling to use it until the official release and want to use a similarly accessible distro in the meantime, Ubuntu would be a better temporary compromise than Mint.

Ubuntu quarantines much of its proprietary software in its "multiverse" and "restricted" repositories. It should not have these repositories at all, and disabling them still does not make it a fully freedom-respecting distro, but it is better than Mint which makes no effort to clarify whether software is proprietary.

Also, you would be able to migrate from Ubuntu 16.04 to Trisquel 8 once it's released without reinstalling.