I like this idea a lot.
Buttercup's suggestion of getting rid of all the casters except for sorcerers in this type of setting led me to a further game mechanic to tie it all together.
If one were to rate all of the small gods on a scale from 0-9, then you could say that by paying the proper respects, prayers and/or sacrifices, you could gain spells from them.
A Clear Fountain (1) in a secluded grove might grant the following spells;
0 -
Create Water
1 -
Bless Water
A Fallen Star (4) that is now worshipped by a band of bugbears in the hills will grant their shaman the following spells;
0 -
Light
1 -
Burning Hands
2 -
Flaming Sphere
3 -
Meld with Stone
4 -
Flame Strike
You get the idea. That way it would behove you character to seek out, and interact with the small gods.