May not a bug, just a thing abaut the new world generation

It was a good change not to have completly different biomes next to each other.But the method having a bug, its allowed to generate 1-2 chunk wide biomes, whitch basicly gives the same effect what we had before.I'm having a mesa, and then a 1-2 chunk wide desert and then a roofed forest.Now, that desert is not enough, the dry at least seems to mix up with colder biomes.I expected more desert or savanna generate araund it.As i written, may not a bug, but it was introduced to dissapear.