Here a proof of concept, still w/o using the information from indentation

This is self contained dual code!

Place the cursor behind the last lisp parenthesis and type C-x C-e and the fat commas will be aligned.

The result is already almost as good as perltidy just way faster.

It's so fast that it could be bound to each return or semicolon key event to align the current statement

$a = {
    bla  => 1,
    trax => [                           #comment
        bla2 => {                       #comment
            sauh1 => 1666,
            3     => 2,
        },
    ],

    bla      => 1,
    _periods => 2
};

my $h_periodsxxxxxxxxx = {
    Mercury => { orbital => 0.24, rotation  => 58.64 },
    Venus   => { orbal   => 0.62, rotation  => -243.02 },
    Earth   => { orbital => 1.00, rotation  => 1.00 },
    Mars    => { orbital => 1.88, rotation  => 1.03 },
    Jupiter => { orbital => 11.86, rotation => 0.41 },
    Saturn  => { orbital => 29.46, rotation => 0.43 },
    Uranus  => { orbital => 84.01, rotation => -0.72 },
    Neptune => { orbital => 164.8, rotation => 0.67 },
};
[download]

you can play around with the lisp code to improve the result.