Pizza crust doesn’t brown

I generally use a fairly wet dough and add oil as well. One of the keys is to keep kneading to a bare minimum. This makes for a lighter dough because it has more air bubbles - kneading kills them. As for flour type, I like '00' type, but there are advantages to other types of flours - as 00 absorbs less water.

If you want to read a completely comprehensive guide to a lot of the factors, this is worth a read...

http://www.varasanos.com/PizzaRecipe.htm

From Encyclopizza

There’s a difference between bubbles formed from under-proofing versus over-proofing. Bubbles from under-proofing tend to be flat but large in diameter. If unpopped, they can blow up an entire pizza. This is the process by which pita or pocket bread is made. Bubbles from over-proofing tend to be high but smaller in diameter. They rise up like little ping-pong balls and eventually form a hole at the top, at which time they stop expanding. They almost always burn. Most pizza bubbling problems are of the under-proofed type.

To resolve a bubbling problem, dough fermentation must be adjusted accordingly. To stop bubbling caused by under-proofed dough, increase the amount of fermentation. To stop bubbling caused by over-proofed dough, reduce the amount of fermentation.

In addition to proper proofing, it has been found that reducing the amount of water in a dough formula can help with reducing bubbling when dealing with the under-proofed type. The reduction in moisture aids in creating the pinpoint holes in the cells walls.

In addition, you want to make sure you properly knead your dough. Some people poke tiny holes in the dough to prevent overly large bubbles. As a final resort you could observe your pizza in the oven and poke bubbles as they form.