now i wish Python had a way to add commands

[Gribouillis]

i'm almost unsure how to have "little" or minimal configuration without setting up a new user. maybe xonsh is overkill for me.

Difficult to answer as we know nothing about your configuration and we don't know why xonsh crashed in your terminal. Does it have anything to do with a fancy linux prompt or 'powerline' ? You could perhaps disable this and try again. Don't give up too early, Xonsh is a very nice tool!