I would barter all of these improvements for a less noisy but performant elemement accessor syntax:

i.e.

  $it->{$key}->[$idx]->{section}->[$i]->{'some.doc'}->method1()->[sub1
+(5)]->method2($x);
  # or
  $it->{$key}[$idx]{section}[$i]{'some.doc'}->method1()->[sub1(5)]->me
+thod2($x);
[download]

becomes something like:

  $it->@( $key $idx section $i some.doc method1() sub1(5) method2($x) 
+);
[download]

Disambiguation: If the actual element is blessed and can('method1'), it is invoked. Otherwise it is treated as a function call (:: might be used for further disambiguation).

I.e. similar to Data::Diver, just more efficient together with a pragma or other method to control auto-vivification. Yes, I am aware, that I could build something similar as a module, but it would be pure Perl.