As an extension of Jenda's post. Instead of making the entire %lglobal hash visible, just cherry pick the bits of it each module needs:

{
    our( $xxx, @yyy );
    *xxx = \$main::lglobal{ xxx };
#    $xxx is now an alias for $main::lglobal{ xxx };

    *yyy = \@{ $main::lglobal{ yyy } };
#   @yyy is now an alias for the array ref in $main::lglobal{ yyy };
#   meaning instead of having to write: 
    for my $i ( 0 .. $#{ $main::lglobal{ yyy } } ) {
         $main::lglobal{ yyy }[ $i ] = 123;
    }
#   you can just write: 
    for my $i ( 0 .. $#yyy ) {
            $yyy[ $i ] = 123;
    }
}
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And you can scope the visibility to exactly the packages, subroutines or just blocks where you need it, giving effectively lexically scoped access to your global data. It's one of Perl's most underrated features.