The huge Gnome 3 schism, that lead to many different Gnome forks. And consequently GTK is more of a Gnome 3 toolkit rather than a universal toolkit, which will affect non-gnome GTK apps.
And if you manage to pick a desktop, hopefully by avoiding Gnome 3 because it constantly changes workflow and uses buggy JavaScript plugins, you realize that you will probably have Gnome 3 installed anyway because apps or the distro having dependencies to Gnome, if you don’t want to settle for old forks of those apps with less features.
And if you didn’t pick Gnome (or KDE) it is a good idea to install a compositor if you don’t like software rendered desktop like the good old Windows 9x days.
Be sure to turn the compositor off if you plan to play any games, especially if you thinking about playing on Wine. Or accept to always play in full screen. This will of course annoy you every time you need to look up something online.
If your game doesn’t run well, just add this unknown PPA that will installs nightly compiled graphics libraries (who wouldn’t?).
And if your computer freezes mid game, sorry you didn’t change the virtual memory size before because it is a fixed size. Tough luck.
And then of course the entire X vs Wayland situation.