I would suggest to provide Windows installer. Most of the users will still use official installer who are not familiar with msys2 and its packaging system.
But as I said above, none of the major contributors use Geany on Windows, even the nice guy who makes the build (and yes with installer) so its virtually untested.
Hmm, I first thought: this probably won't work as it would require users to install MSYS2 in order to install Geany within.
On the other hand: maybe there is a way to use MSYS2 packages directly without installing a full Linux like environment. And it would save me from moaning about Windows build and installer issues :smile:.