Well the other major inspiration for the style comes from Legend of Mana which has a very curvy art style.
Especially looking at the doors and walls.
So I guess my main point is that I want the game to have a fantastic feel. Something a bit otherworldly, like a structure you know shouldn't be standing because of its dimensions and yet is. Overall, Black Cauldron, Legend of Mana, Curse of Monkey Island and Whispered World are all big inspirations behind my background style. But Black Cauldron more than any of them I think.