My life is in Ubuntu linux installed in Oracle Virtual Box on a Windows host. I'm a Ruby on Rails developer.
2 24" monitors + the laptop monitor. I don't care much about my mouse as long as its large enough. I honestly don't touch my mouse that much. My keyboard however is my prized possession. Daskeyboard mechanical with brown switches in it. Absolutely love it. If you are keyboard jockey, well worth the investment in mechanical. Just don't get the red switches or you will drive your office mates nuts.
Good primer on mechanical keyboards:
https://www.pcgamer.com/best-mechanical-switches-for-gaming/
P.S. VIM and Emacs are for dinosaurs. Sublime fo-EVAR