Hm, that must mean everyone I know is using zsh and I didn't realize that... that strongly suggests I should use it too!
https://github.com/sorin-ionescu/prezto https://github.com/zsh-users/antigen See also: https://github.com/unixorn/awesome-zsh-plugins
while bashims may give additional features, readability and portability suffers. I much prefer scripts using a posixish #!/bin/sh and a strict subset of shell syntax. something like pdfx.
I use fish for scripting but run zsh for terminal. (fish had couple weirdness in day to day terminal use and zsh could do pretty much all fish could do with zplug.)