Personally I love Mesas, I love when I start there and my character finds an oil well not 500 blocks away in a wasteland... so awesome.. I love mars like worlds for some reason that's why I make them in Mystcraft. My best ever was starting in a mesa with a redwood forest (natura redwoods) right next to it with a river biome with a massive oil field in the center lake. and crags over looking that. I built bases in every one of those biomes dedicated to different mods like thaumcraft, railcraft, buildcraft all sorts of TE stuff mixed in and just tons of fun.