I have a small collection of different trackballs from different generations and I love them all. I also use a cheap standard mouse in my daily life and steering through my Linux world and I'm happy. I'm also using i3 or dwm again nowadays, depending on my mood, and also writing again a lot of stuff in vim (and LateX or groff). This leads to the situation, that you have to use the keyboard for most or all commands and movements.
As somebody, who has started with DOS in his youth and also learned later for example AS/400 stuff and similar, I always liked this way of "controlling" a computer, but I also created and worked with a lof of graphics, video and photo stuff later in my (work) life and there is a mouse essential. But the time has changed again and my private life today is filled more with watching, writing or reading content, so back to the good old school digital life and slowly and step by step I change my general hardware computer setup to the same level - or let's say: welcome low-tech again. Welcome 80-90s style again.
This means working in the terminal as standard and using keyboard commands wherever possible. For simple stuff, normally I use Links2, which is a great and neat text based browser for Linux, but for other stuff I finally switched now (most of the time) from Firefox to Qutebrowser. This Python based browser supports vim keybindings and also configurations like do not load images by default and stuff like that... it also works with Youtube, which is somehow important for some channels, that I like to watch. So it's really nice.
To see, how well I (still) can deal with that as an old school boy with 42+ years and slowly weak memory, I've put away the mouse from the table for now and just using the keyboard for everything. I like this kind of personal challenges, even if they have no real important impact to my or the life of other people... but it's still fun. We will see, if I will change the setup again or continue this path and reduce the amount of equipment. A clean table with just a keyboard is a kind of "level", that I really would like to reach again. And also to write more, like 20 years ago.