Personally I wouldn't use a full-on replacement interactive shell because I have a stacked .bashrc that I've constructed over a long time, and things I install

Personally I wouldn't use a full-on replacement interactive shell because I have a stacked .bashrc that I've constructed over a long time, and things I install from my package manager all come with bash_completion support etc, and even scripts written in Python can vend bash completions (https://pypi.org/project/argcomplete/ https://pypi.org/project/argcomplete/). Also shellcheck's static analysis of scripts is very educational and that feeds back into interactive use. I like that you support the scripting use case with vanilla Python syntax. That's something that made Xonsh a non-starter for me (I'm not going to write scripts when syntax highlighting and auto-formatting don't work because it's a superset of valid Python syntax). Evidently my definition of "going off the deep end" here is giving up lots of working tooling and integrations.