The freeware utility ShowOff should meet your requirements.
The key difference from the other tools you mentioned is that only the most recent keypress (or key combo) is displayed.
By default a key is displayed for 1 second but this is configurable. To represent holding down a key in your gaming scenario set the timetoshow parameter to greater than length ...
AutoKey can use a hotkey on the number pad, and it's scripts can definitely paste text, for a super basic example with this in a script:
keyboard.send_keys("Send these keys")
It's Beginner's Guide says this:
What Is AutoKey and How Does It Work?
It is a trigger or selection activated, automation utility program for Linux and X11. When a trigger is ...