True, if I ever need to use ghostscript (whatever it is) in my day-to-day life, it'll be a trainwreck.

It's a ps/pdf toolkit type program. It is used by imagemagick as a backend for pdf conversion type stuff - so if you every need imagemagick you might find yourself in for some annoyance as well.

Aliases are only expanded in interactive shells so ImageMagick or any program that calls an executable from within a process will not have any issues.

You can, you just have to prefix them with a hyphen, e.g.:

  $ -gs

I'm actually using them as git aliases, not bash command aliases.