I will say right off the bat, it sounds like you know a bit more about me, so whatever you decide will probably already be a pretty informed choice.

With that said, having used ubuntu occasionally in the past, it doesn't feel all that different from Debian. They are roughly equally functional, performant, etc.

Before I found Debian Mint, I wrote a script for base Debian 12.2 to auto-install

I probably should do something similar, because down the line who knows, I might need a full re-install.

because I have no idea what I could be missing in the background on my Debian install, or didn’t set up correctly because I don’t know about it.

Very anecdotally, like I said there has only been two programs that I haven't been able to get running that I really want. That's fusion360 and dungeon draft. Both of which I could pretty easily get running in a VM.

Actually now that I think about it, there is a 3d program, and that's fortnite. But that's because their management doesn't give a flying fuck about linux, and so their anti-cheat breaks the game. So no distro will be safe from that.

I also noticed that Debian Mint currently uses a newer kernel than Ubuntu Mint

Again, it sounds like you are much more informed about it than me. But personally, it hasn't made a difference for me. I can run my games, the basic internet browsing apps that I like, etc.

Has there been any particular thing you had to do to Debian Mint to make it work better for you?

The most complex thing that needed set up was getting my drives auto mounted on startup. But debian mint has a pretty straightforward way of setting it up, so it took maybe 5 seconds.

Beyond that, it's just been a small bit of effort setting up the programs I use. Steam, freetube, the prism minecraft launcher, my nvidia drivers, cura, KDE connect, gitkracken, vscode, vlc, etc. It is really low effort honestly, basically the same effort as windows. The software manager/library on debian has been pretty decent to me.