Sirius reminds me of a favorite uncle who lays out under the stars with you as a child and listens to your dreams and takes you on motorcycle rides that worry your mother. You adore him as a child.

But when you grow up, you understand why your mother was so frustrated with him. You still love him, but you wish he'd just get with the program because he has big plans and big dreams and yet doesn't ever seem to be working toward them.

I think you've captured this beautifully.

And the question becomes if Sirius had the right influences, would he have turned out differently or would he be the same? Can Harry and a grown up Remus make a difference?