For what it's worth, I run i3 on my work laptop and I don't have any issues with those things - the only config I've done for multiple monitors is configuring o

For what it's worth, I run i3 on my work laptop and I don't have any issues with those things - the only config I've done for multiple monitors is configuring one to be vertical and binding workspaces to particular monitors. I didn't go for a clean install with no desktop environment, though. I started off with a standard Ubuntu 18.10 install and then installed i3, so I can still start a session with either i3 or gnome. Highly recommend this setup - it makes everything pretty easy because you still have all of the default apps and settings from Ubuntu. The only real config weirdness I had to deal with was adding keybinds for volume/media keys, and the fact that the display brightness keys on my laptop aren't bound (I always run on 100%, so it doesn't bother me).