There are roughly 500 points to a rank with each rank being the same number of points (or roughly the same number of points) as the previous rank. Easy quests 10 points, Medium Quests 25 Points, Hard Quests 50 points, Insane quests varies. Look around the site a bit and you should be able to deduce it more precisely. (You might even call it a puzzle game.)
Insane quests seem to give around 200 ish points but I think they can go up to 250. You can spend some time on the hero board going to people that just hit a new rank and you can see the points there.
