Personally I use a smaller keypad with a lot of
ctrl+ [key]
shift+[key]
alt+[key]
double [key]
and a gaming mouse with lots of thumb and finger buttons for the essential stuff.
These are discontinued but I buy them on ebay when they come up - currently I have 3 - just in case!
https://www.amazon.co.uk/WolfKing-Warrior-Black-Gamepad-Keyboard/dp/B000IMZHL2
There are probably better options on the market today.
mouse buttons:
aim / fire/ enter or activate or use
backspace (close menu)
walk/run toggle
grenade
freelook
for flying i use
Q/E as nose up and down to aid me in sharp turns
dbl SPACE as eject
dbl W as toggle autohover (almost never use it)