Keyboard controls are pretty good, but there are a few things that could use a little polishing...
Currently, we can't remap the key for "holster weapon". The default is double-tap-ALT = holster-Weapon, which is problematic as single-tap-ALT is switch weapon and it's far too easy to miss the timing for a double-tap and unintentionally switch weapons. How about hold-R = holster-weapon? The worst that can happen is that you accidentally reload a weapon, which I don't think would bother anyone.
Accidentally switching weapons is bad though, and timed/auto-holstering a weapon (like was added in patch 1.3/1.31) is very immersion breaking as you're constantly holstering/unholstering. (If you've drawn your weapon so that you have it at-the-ready, there's probably a reason for it... You might relax and lower your arm slightly after a while, but you're not going to put the weapon away entirely while there's still a threat nearby.)
Switching from Cyber-arm weaponry to ordinary fists also needs some improvement. Currently, if you hit 4 to switch, it always goes to the cyber-arm weaponry, and there's no way to select ordinary fists with just a keypress. How about if you're using weapons 1/2/3 and you hit 4 it goes to the cyber-arms, and then for each additional press of 4 it ping-pongs back and forth from fists→cyberArms→fists→cyberArms? That'd be a lot more intuitive.
Crouch-toggle is fine, but there's a related problem in that when you're toggled into the crouching position and walk over uneven terrain (like and air-conditioner, cables, piping, garbage, etc), it sometimes causes V to stand/crouch/stand/crouch/stand/then re-crouch... which removes the dark vignette from the screen for a split second each time you stand, causing a disturbing flicker. Why not tie the vignette to the key-toggle rather than the player-animation, so that the vignette stays active/dark even if V stands for split second while moving over rough terrain? That flicker is really nasty and must be fixed.
Currently, we can't remap the key for "holster weapon". The default is double-tap-ALT = holster-Weapon, which is problematic as single-tap-ALT is switch weapon and it's far too easy to miss the timing for a double-tap and unintentionally switch weapons. How about hold-R = holster-weapon? The worst that can happen is that you accidentally reload a weapon, which I don't think would bother anyone.
Accidentally switching weapons is bad though, and timed/auto-holstering a weapon (like was added in patch 1.3/1.31) is very immersion breaking as you're constantly holstering/unholstering. (If you've drawn your weapon so that you have it at-the-ready, there's probably a reason for it... You might relax and lower your arm slightly after a while, but you're not going to put the weapon away entirely while there's still a threat nearby.)Switching from Cyber-arm weaponry to ordinary fists also needs some improvement. Currently, if you hit 4 to switch, it always goes to the cyber-arm weaponry, and there's no way to select ordinary fists with just a keypress. How about if you're using weapons 1/2/3 and you hit 4 it goes to the cyber-arms, and then for each additional press of 4 it ping-pongs back and forth from fists→cyberArms→fists→cyberArms? That'd be a lot more intuitive.
Crouch-toggle is fine, but there's a related problem in that when you're toggled into the crouching position and walk over uneven terrain (like and air-conditioner, cables, piping, garbage, etc), it sometimes causes V to stand/crouch/stand/crouch/stand/then re-crouch... which removes the dark vignette from the screen for a split second each time you stand, causing a disturbing flicker. Why not tie the vignette to the key-toggle rather than the player-animation, so that the vignette stays active/dark even if V stands for split second while moving over rough terrain?
That flicker is really nasty and must be fixed. 
