"You don't have to stick with the default."
Technically this is true, but everyone who's actually experimented with installing non-default DEs knows it's not as simple as that. Unless you do a bunch of maual config and debugging, a non-default DE never works as smoothly as the default. Plus, adding a whole DE and all the packages and dependencies it needs adds a lot of bloat to your system. For anyone who isn't a power user who enjoys spending hours fiddling around under the hood of their PC, and doesn;t mind putting up with random bugs (admittedly this does describe most of us on this forum), I'd always recommend finding a distro/ version that has the DE they want as the default.
This is why I'm really pleased to hear that Trisquel 8 will use Mate as the default, rather than the increasingly bloated GNOME Fallback. It's just a shame they're staying with LXDE, with its appalling Midori browser, instead of taking up the chance to be the first libre distro with an Enlightenment E17 version.
