I think that the percentages are very fair. The vast majority goes to the people who spent the time and money to actually make the game. This makes it easier to get new games to put on the site, and makes it so the indie devs can keep eating. 15% for the Humble guys isn't bad. They host the DRM free copies if I'm not mistaken, which is a decent chunk of bandwidth. And they obviously want to get paid too, since this is basically becoming a sales platform. 10% to charity is still a good amount. It's not huge, but it's not insignificant either. As the front page mentions, they've raised over $72k for charities already.
That said, I do think you should be able to spread your donations out however you want. There's no real reason not to as far as I can tell.
The main thing to keep in mind though is that, while a part of the Humble 'brand,' this is not the Humble Bundles. This is a storefront, which makes things change.
That said, I do think you should be able to spread your donations out however you want. There's no real reason not to as far as I can tell.
The main thing to keep in mind though is that, while a part of the Humble 'brand,' this is not the Humble Bundles. This is a storefront, which makes things change.