When comparing <Space> vs ; (semicolon), the Slant community recommends <Space> for most people. In the question“Which key works best as Vim leader?” <Space> is ranked 1st while ; (semicolon) is ranked 5th. The most important reason people chose <Space> is:
In most keyboard layouts it is the biggest key and is reachable with both hands easily.
Ranked in these QuestionsQuestion Ranking
Pros
Pro Easily reachable with both hands
In most keyboard layouts it is the biggest key and is reachable with both hands easily.
Pro No need to move your hands away from home row
Pro By default, <Space> does the same thing as lowercase `L`
Pro Pairs well with hjkl and easymotion moves
With easymotion binds, it's one of the fastest ways to move through a document, e.g.:
;l => easymotion-wl
;h => easymotion-bl
;j => easymotion-j
;k => easymotion-k
This isn't fast with space as leader.
Pro Somehow significant faster than space
I had space for a year before I switched and space works well for one hit keys but using it as a starter for a combo doesn't feel fluid
Pro Located on the homerow
Pro Space can be then used for major or often used things like FZF
Pro When using clever-f you don't need ; anymore for f movement
Cons
Con There are better uses for <space>
It is better to use space for EasyMotion. This is an important key that's rarely used.
Con Space feels clumsy once you use it in combos, as a single hit key it's great
Use space for stuff you use all the time (eg FZF), once you try combos it feels super odd. I guess the thumb is just a different animal than the other fingers...
Con Space is commonly used to toggle folds
For those who use folds a lot, a common mapping is:
nnoremap <space> za
Not a problem if you don't share your editing session with anyone else of course.
Con Shadows important movement
Repeating last "f" or "t" is a useful movement.
Con Remapping comma or semicolon may limit the f and t commands
You'll lose the default behavior of repeating the f and t commands: ; (semicolon) repeats f, F, t or T command. ,(comma) repeats f, F, t or T command in opposite direction.