In terms of shell, I moved to the fish shell 5 years ago.

Things are so much easier. No need to a massive amount of plugins and configs, mostly works out of the box.

Fish is probably a good idea for an interactive shell. Osh/ysh might be a good idea for scripting:

https://oils.pub/

I'm still using bash out of habit, though. My one nod to modern tooling is using fzf for shell history search...

xonsh user for 8 years here :-)

I agree that these shells are better than bash, etc. But some bash knowledge is probably a must, given its ubiquity. You're not always going to have the option to install fish.

(Sadly, most of my jobs, including my current one, require tcsh).