> For everyday usage the core ash shell is perfect for scripting
In my experience, most people have great difficulty correctly writing a simple loop to renames a set of files in a directory. I sumultaneously appreciate UNIX philosophy, and think the shell can be much improved by moving away from POSIX.
Even erlang can be a shell and wrap around the system toolset making your basic shell scripts work concurrently.
For everyday usage the core ash shell is perfect for scripting and zsh csh or korn for interactive usage.