> "spit out a warning if you created a branch and then try to commit to master"

How this one may be done? It sounds wonderful but I have no idea how to implement such thing (and if not included in git already, I hope that I can reuse code rather than reimplement it)

Oh, hey now. Look at the very bottom of the resource I sent you, under "Snippets" https://githooks.com/

"A pre-push hook that prevents direct code push to master branch"

and I would want

"spit out a warning if you created a branch and then try to commit to master"

Sometimes I would want to commit to master, I want an overridable warning iff I just created branch.

How about

  #!/bin/sh
  BRANCHES_POINTING_TO_HEAD=$(git branch --contains HEAD  |wc -l)
  CURRENT_BRANCH=$(git branch --show-current)
  if [ "$BRANCHES_POINTING_TO_HEAD" -gt 1 ]; then
    if [ "$CURRENT_BRANCH" = "master" ]; then
      echo "You're committing to master even though other branches exist."
      echo "override with git commit  --no-verify"
      exit 1
    fi
  fi

You'll need git 2.22 for the --show-current git option.

But also I would suggest instead using

  git checkout -b <new_branch>

to create and switch branches in one command

A better UX would be

    $ git checkout <new_branch>
    <new_brach> doesn't exist. Would you like to create it (Y/n):

The real problem with "git" is just way too many options. For automated tools there can be a "-n" non-interactive option that fails with an error code and doesn't ask questions.