Idea: The color of the grass/ground in the biome you're in (somewhat) determines the color of elite monsters and elite items.
So, say you're in a cold biome, with cyan ground, you'll get a pollywog with white skin, blue eye, and black feet, etc. etc.
That way there could be like "Winter" Themed areas, "Hell" themed areas, "Forest" themed areas, etc. etc.
also make spiky bushes and peanuts more common, I hardly ever find them