It would be great if the criticism that accompanies "Show HN" posts was more useful and less vicious.
It is one thing to provide constructive criticism. It is another to be condescending. Unfortunately, and maybe it is just human nature, but I think we see too much of the second.
I'd love to see more help in getting projects off the ground. That would be a great compliment to Y Combinator. Since many Y Combinator alum are on the site, they could use their experience to help HN contributors who aren't in the YC program.