In this vein, I set my PS1 to bold red capital letters on bastion hosts and alias sudo="echo 'You're on a jump box moron :p'"

I do the tmux color trick too-- color coded by environment for each bastion.

Something like this to obviously distinguish environments is good practice - at one company we implemented scripts for terminal color-coding like this after some downtime caused by a destructive backup restore accidentally being run in the production environment instead of an acceptance testing system, which was in all aspects identical to the production system.

And I've seen a solution for more secure environments where physical separation was used with the operator having separate monitors/keyboards, and the "important" system having a different color keyboard and monitor frame.

That's nice — I usually start my commands with `# ` but then there's no tab completion. I'll try `ls`

We do this for our database connections in Azure Data Studio / the Windows version of it. Really great idea.

I usually use echo for the same purpose.