You might want to look at Test::Class and the section on "Extending Test Classes by Inheritance".

For a more manual approach, what I've often found helpful when I feel like I'm needing identical tests is just creating my testing functions in a helper module that takes an object to be tested (or even just a class name) and a prefix for the test label.

# file: t/helper.pm
package t::helper;

@EXPORT = qw( run_all_tests );

use strict;
use warnings;
use base 'Exporter';
use Test::More;

sub run_all_tests {
    my ($obj, $prefix) = @_;

    diag "Starting tests for $prefix";
    
    isa_ok( $obj, "Parent::Class", "$prefix: object isa Parent::Class"
+ );

    ok( $obj->true(), "$prefix: true() is true" );

    # more tests ...
}

1;
[download]

# file: t/001.t
use Test::More 'no_plan';
use t::helper;

my @cases = ( 
    Parent::Class->new(), 
    Sub::Class->new(),
);

for my $o ( @objs ) {
    run_all_tests( $o, ref $o );
}
[download]

Does that do what you were looking for? Or did you mean something different by "comprehensive output"?