This is not an attempt to argue with your feature list. Bash clearly doesn't do some of those. But I just noticed the for one-liners you mentioned. I do that in bash alot actually. This is just fyi for anyone reading, not trying to argue with your feature list.

for f in *.py; do wc -l $f; done

also, you can do something like

for f in `find project_name`; do wc -l $f; done t work on the output of another command.

Cheers!