I also prefer tri shorts to heavily padded shorts. The Zoot Endurance shorts are stretchier and fit my curves better than the Ultras (which fit like a sausage casing for me). My favorites are the DeSoto shorts, but they are an acquired taste. They're cut pretty low on top.

If you want more padding than just a tri chamois then look at DeSoto's 400 mile shorts. The padding actually has a channel in the middle, like a saddle cut out.