Computer freezing on startup with gdm3 after possible package issues
Solution 1:
Some kind of solved:
After continuing to delve into the problem, I realized that xserver-xorg-input, and xserver-xorg-input-hwe weren't installed.
So I installed the meta packages for them, and the system seems to be, for the most part, working. Some small bugs here and there, but my initial issue is solved.