My understanding is that automount is different from what you’ll need. The automount that you’re using is probably mounting when you log in, but you’ll probably want to mount when you turn on the computer.

For that, you’ll want to edit fstab. That’s a file that tells the system that you need to mount this drive during boot-up. On KDE, there’s a partition manager software that can edit fstab through a GUI, but I’m not sure if there’s something similar in Mint. If not, the file is in /etc/fstab. Make sure to double check for typos when you edit fstab because errors can prevent your computer from booting up properly. Or just be proficient at terminal so that you can undo the changes when you make an error.

Word of advice: use the nofail option for secondary/storage drives

Not finicky and Arch-based don’t really go together well.

Just go with Bazzite or something, the exact distribution doesn’t matter (as long as it’s not Arch). The more important choice is the desktop environment, which is the user experience and looks of the distro. If you’re moving from Windows, I assume you’ll like KDE Plasma. It’s basically Windows 10 but modernized, with a more aesthetic and clean look. (It’s also paralyzingly hypercustomizable, so I would recommend using the default settings initially and slowly learning the settings, rather than diving into the settings headfirst the moment you install)

I personally use Kubuntu (Ubuntu with KDE Plasma), but it’s slightly more annoying to set up than something like Bazzite