In standard Vim you use the Escape key to switch from Insert mode to Normal mode. You use this key very often and it quickly turns out that the Escape key is not in the best position: it is very likely you use your left pinky for that, which “pulls” your left hand from the home row.
One family of alternatives you will quickly find is the key stroke ‘jk’, or ‘fd’. The latter is used by Spacemacs but to me its implementation does not seem ideal. I think the Hydra package is used, which first displays the two keys and only then recognizes them as a single key stroke. This temporary display of the two keys causes some flickering, which you will see each time you switch to Normal mode.
An alternative approach is to remap the CapsLock key to Escape. I already have remapped CapsLock to Control for Emacs and, at least for now, I would like to keep it like that. Fortunately in Linux a tool exists that allows one to remap CapsLock to Control when it is used in combination with another key, and to Escape otherwise. This tool, named xcape, is present in the Ubuntu 16.10 repositories.
After the installation of xcape, I used the following two commands to assign the dual functionality to CapsLock:
# set Compose key and remap CapsLock to Ctrl $> setxkbmap -option ctrl:nocaps # make short-pressed Ctrl behave like Escape $> xcape -e 'Control_L=Escape'
One final note, the use of xcape is not my idea - I did not even know the tool existed. Some Googling for alternative keys for Escape quickly lead me to that solution.
The Spacemacs Org layer introduces several key bindings but unfortunately also overrides standard Vim bindings. In Vim, when you press ‘t’ (in Normal mode), the cursor moves to the position right before the character that follows the ‘t’ command. In Spacemacs, when you press ‘t’ the type of the current headline changes, e.g. from standard title to TODO. I am not that fond of changes to standard Vim key bindings, especially not now while I am trying to become proficient in Vim.
It turns out that minor mode evil-org-mode brings along the new key map. I could disable evil-org-mode, but this might be rather drastic. I could also restore the bindings of the keys that trouble me. For now I have decided to leave everything as-is. If the lack of ‘t’ (or other keys) turns out to be troublesome, I will handle it then.
In case I do decide to disable evil-org-mode, note that the function of the same name is added to org-mode-hook in evil-org.el. To disable it, I can remove it from the org-mode-hook in my .spacemacs.