=head1 1. post-3.0.0: HALF-DONE: Add hashes, simple enough syntax 

	--hash.=name=value, or just --hash=name=value

I think I prefer the former for consistency, --hash=name=value sets the whole hash to the single pair.
Also, there will be hash-=name to delete an entry; perhaps hash+=name=value as alias to .= operator ... but then, would that prohibit other meaningful use of those?
Hm, I don't define those for arrays ... but one could indeed define -= for removing elements (positive/negative number for pop/shift).

=head1 3. post-3.0.0: consider supporting environment variables ...

perhaps ... in the form PROGRAM_PARNAME

=head1 4. post-3.0.0: Consider proper parameter groups

buntstift has tex.* parameters ... looks like a group, but is none. Do I need extra structure?

Perhaps all that's needed is in config files, mimicking INI-style grouping via

	=prefix tex.

(without or without dot ...)

That would prepend "tex." on all the following parameter names. Config::Param::print_file() could get some smarts to detect common prefixes. And done you are with pseudo-groups.

I could even add [tex.] as alias for that and, when avoiding here-document multiline strings and meta stuff, would have something that should parse as INI.

=head1 8. post-3.0.0: $config{hidenonshort}

consider providing a list of those instead ... or in addition, at least
