I stumbled onto a really nice one. Kind of annoying jungle area, but there are lots of dimond and other goodies. It's very iron and coal rich. There are all bioms, though some are small and a good bit of water. No villages tho, but it makes up for that in resorces.
X 41 Y42 Z85 Has a nice dongoun with an end portal and library. (There may be more, I haven't fully explored it yet.)
X -280 Z326 or X-250 Z181 is a good point to start digging down to search out the dimond, gold and lots of redstone, iron and coal. But be warned that there's also alot of lava so be prepared with a bucket of water.