Here's a question System V or BSD ? lol
When I started using Unix (Dec Ultrix) there was no bash, there was sh and csh and I could do so much more in csh.
The thing I liked most was command line completion.and cdpath which I could type cd bin and change to /usr/local/bin instead of /bin or which ever way I set up cdpath. Also aliases (are you seeing I don't like to type ?) lol
I prefer csh thus tcsh, but I use both and whatever fits the job, I like faster easier. After yeas I carried around a floppy with my .cshrc file because I had so many aliases, it slowed me down if they weren't available. lol, now a days bash has much of the same features so I think it's tomato tomahto. one thing I never understood with sh, is why did they use the word export, set and setenv seems much more logical.
This link has a good explanation of some of the differences and history.
If I tell you I use perl are you going to ask why not python ? lol
:-)