Seeing the GitHub repository of i3 and sway, sway has more stars than i3. But both seems well-maintained. I have been using i3 on my ThinkPad Carbon, and now customizing the i3 on my Framework Laptop.
This Youtube video Tiling Window Management and i3wm config additions introducing i3 is informative. It seems the person has long experience of window managers.
And he is sharing his heavily customized i3 config at his GitHub repository.
Here is how to see it. As he stopped supporting i3, you need to check a past commit.
$ git clone https://github.com/LukeSmithxyz/voidrice.git
$ cd voidrice
$ git checkout ad161d9363aadeb9f4ec3c852ca6c96162f2b4b0
$ vi .config/i3/config
This person’s Youtube play list about Minimalist software looks nice.