Chaoskin, if you look around the first couple pages of the boards, you'll find a really long thread I posted titled Hide and Seek. This has a clarified system for everything that touches Stealth and invisibility, including light and darkness.
There's still no level above bright light in that system either, though. Easy to add if you're GMing, though - just use the dazzled condition as a basis for most creatures.
I was looking through your "hide and seek" post and still have questions.
A torch has the effect of raising darkness to normal light in the immediate 20 feet but that's 2 levels not one. Darkness to Dim to Normal. So while Light changes the condition 2 levels in the immediate 20 foot area and 1 level further out, Darkness only appears to lower the light 1 level. Is this because it would be too powerful if it was equal?
The eclipse spell feat says that it basically reverses the Light spell but that would only be true if torches cast dim light or if the eclipsed version of Light lowered it 2 levels in the immediate area and 1 level further out.