The frequency at which the ores spawn in the end is way too high in my opinion. Since it doesn't have too many uses at the moment (that I know of), I would suggest to turn down the default values by a lot, especially considering all the new islands in the end now in 1.9.

I'll keep that in mind. I'd like to reach the End in survival once on my own to get a feel for it. Then I'll tweak the defaults.