You probably know this, but Mint is kind of just Debian with extra stuff (some might call it bloat, but that’s a matter of use case). So a switch to Debian from Mint should be very straightforward, if not seamless. The package manager is the same, and that’s usually the biggest part of switching distros. Debian is also ideal for hosting specifically; many, many production servers run on Debian. It’s also arguably the best-supported distro out there, so whatever question you have had probably already been answered.

TL;DR you should totally try Debian out (especially a headless version). It mostly like won’t be an issue.