The first is drawing at X's borders when having multiple panels connected leads to flickering and graphical artifacts. This means triggering any window/video to go full screen while you have output on more than one monitor. It's not a unique problem to i3, but most other WM's handle window drawing in a different manner.
The other issue I find more annoying. That's tearing while scrolling and playing video unless a compositor like compton is run. This appears to not be a problem for a lot of people, in the way that using frame interpolation on tv's doesn't bother them. For me though, it drives me nuts. Compton by the way hasn't had development in over 3 years.
I just don’t want to think about how to move incredibly quickly around the computer. Easy point and click is all the effort I want to muster, sometimes.
Right. This is an important thing to note.
It takes a lot of mental energy to remember all of these things if they are not already imbued into your brain as effortless muscle memory. Sometimes that energy is better off spent solving the problem you're trying to solve. This is why after about a year of using Vim, I still use the mouse once in a while.
I remember once reporting a bug with the Microsoft Terminal (I use WSL 2 on Windows) on Reddit and when I mentioned mouse support didn't work inside of programs like Vim, it was the most down voted comment I ever created on any platform with swarms of folks saying I wasn't using the terminal as it was supposed to and that I must be an idiot for wanting to select text in Vim with a mouse.
Luckily they fixed the bug (it ended up being one of the highest priority bug fixes they had).
I also had the issue of a limited keyboard and shortcut keys. I use a Kinesis advantage. I don't have a windows key. So I used alt as a super key. This meant that I often couldn't use application shortcuts. It was a major pain. In hindsight I should have mapped in a windows key and sacrificed one of my thumb buttons for it.