With EXWM, X windows are Emacs buffers and rendered inside of Emacs windows, so you switch between X windows the same way you switch between Emacs buffers; you use the same tiling system for both Emacs and other programs, so you don't need an extra set of key bindings, etc. It's a very nice unification.

Does emacs have a common leader key set up ? I’m new to emacs

It can, and a significant part of the community uses that setup including me. You might be interested in checking 1. Spacemacs - http://spacemacs.org/: A config for emacs with starter packs. They have a good collection of leader key and vim bindings. 2. evil mode and evil-leader - Well integrated standalone vim emulation and leader key.

I personally started building into vim keybindings in emacs via spacemacs, and then over time created my own config with the features I needed from spacemacs (which is much more than just vim emulation).

PS: Should also mention https://github.com/noctuid/general.el. I don't use this one, but it is pretty popular too.

Thanks! I hopped ship from vim to emacs recently precisely because my vim setup was getting super bloated from adding hacky extensions to try to make it like an IDE. Trying to set up an ide per language in vim is an exercise in frustration.

I guess I made a good choice since emacs is able to integrate an x manager (lol).

The issue for me is my tmux leader is Ctrl-f and my vim Ctrl-p uses ctrl-p.. ctrl-d and ctrl-u are used in vim for page up and down. And some other nice Ctrlkeys are taken by vim as well. I will need to carry these key bindings into emacs evil mode...

So Really running out of good leader keys I can use !

I started on evil-mode only. Heard about space macs but I wasn’t sure how well it could work with emacs ide-packages such as SLIME for lisp (and I will want to find emacs ides for Java, Js, Python, C, Cpp, ruby, Ocaml - any suggestions here much appreciated as well)

Also consider https://spacevim.org/ (inspired by Spacemacs)

or, avoid spacemacs & spacevim, and just install evil-leader, evil-surround, and evil-matchit. Emacs starts up faster in this case too.

Recommendation to a former Vimmer who wants to try Emacs to avoid Spacemacs IMO is irrational. Spacemacs and Doom-emacs are the best things to try. Spacemacs is well documented, community supported and extremely popular among former Vimmers. Trying to learn and configure Emacs from scratch usually does the opposite effect - an overwhelmed person gives up and runs back to the comfort of the familiar tool.

My guess is “even more keyboard driven”.

I am currently a happy i3/neovim/Mate User, but this looks really cool