Al,
Really glad you like the Caputo! PF's recipe is 59% (500/850) hydration and your proposed recipe is 50% hydration (500/1000), both in baker's percents, of course. That's a little low, in my opinion; as you know from my pm, I do 65% hydration doughs with Caputo. Tough to handle, but well worth it in end-results, if you ask me. Good neapolitan pizza places use wooden boxes for the final for the "appretto" stage (individual dough-ball proofing) which I think helps in making the dough balls a little drier on the outside, without forming a crust. That should make them easier to handle.
As for oiling the dough balls, that's a no-no according to the purists. The reason behind it is that the oil burns at the high temperatures and tastes bitter. The best way (outside of using wooden boxes as per above) is to use Varasano's method of putting the dough balls in 3-cup (or so) glad containers. Oil them with only a drop or two of EVO as a release agent and that shouldn't make your dough bitter.
To prevent the crusting in the "punto" or "puntata" stage (the mass proofing), I put the dough in a bowl and cover it with plastic wrap, with the plastic touching the dough completely. Then I cover the bowl (not the dough) in plastic wrap too. This is so that if any area of the dough gets un-covered when the dough rises, it will not get too crusty in that area. It seems to work for me.
By over-extensible do you mean that it was too elastic (ie, it won't stretch properly)? I find it strange that a 59% hydration dough would be too extensible. Chewy, I understand, I would expect that because of the low hydration. The other thing you can do is to knead the dough less. I just recently started kneading by hand and I find that stopping soon after the dough gets smooth and starts sticking less is when you need to stop. Neapolitan pizza should be very delicate, so over-kneading is to be avoided. As mentioned, the hydration also plays a large part in that.
BTW, any pictures???