This can be done if a new tool ( replacement tool) is introduced into cubase with/without key modifiers
we were doing that. My keyboard note selections are similar to yours! I use 0 for whole tone, 1 for half-tone, 2 for quarter tone ( more logarithm to the base 2 approach).
You are using computer keyboard. I have played piano for years and using either step recording ( for fast passages & chords) or midi input is more efficient for me. For note entry, we always need to use key editor at some time for detailing jobs. Thank you for your comments.