The only option I can think of would be to use a vm. Unless all your apps support restoring sessions, I don’t think there’s any mechanism to do so globally. Getting stuff to start automatically or as a group using a script is easy enough, but that’s less than half your problem as you’ve described it.
Debian netinst. The network installable iso is much smaller than the full image as you only download stuff you actually want to install. Ubuntu used to have a mini.iso but sadly they got rid of it AFAIK.
If that account only ever logged in there, maybe? I’d think they’d be smart enough to look at the most commonly used IP address by the account(s) in question. Then again, it is reddit.
If your setup allows you to be a productive member of society, you’re golden mental health wise. /s
You may want to get your eyes checked if watching HD video on a tiny screen seems preferable unless all your content fits your displays native resolution; I am fairly certain my eyes are terrible. Maybe that’s why I love that dark themes are becoming more popular.
Transparency is nice, but Windows Vista is partially what converted me to Linux. I dislike rounded corners too, since content is always rectangular.
I don’t know why no mainstream desktop OS really has a good mouse driven tiling setup out of the box. I have a dual screen setup, so I mostly just full screen apps and alt tab if needed which reduces distraction. If I’m trying to focus on a single thing, the second screen gets turned off.
I find myself becoming more minimalist over time as well. Society seems to be more distraction driven by the day, so having an OS that stays out of the way is a boon.