Nice technique. It seems to me that it's a handy step on the way to splitting things off into modules and/or object-oriented bits. Since all the references go through your global hash anyway, when you split off a function/module/object, the code in your subroutines wouldn't have to change much:

BEFORE

my %my_global_values = (foo=>0, etc=>0);
my $rGlobals = \%my_global_values;
sub zigafoo { $rGlobals-> = 7 }
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package barbaz;
my %my_package_values = (foo=>0);
my $rPackage = \%my_package_values;
sub foobar { $rPackage->{foo} = 7; }
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