I would say material, temperature/firing type, and post processing(branding/photography/fees/etc), should all factor into how you price. Once you have figured out the "cost" of the piece, then you can go in and add things like, how much you would like to make per piece, or per hour.
I like math so I usually have a basic equation in my head, something like this:
cost of materials (clay, glaze, slip, lustre, decals, etc)
+kiln costs
+studio fees
+etsy fees/vendor fees/ taxes
+photo & editing (not a big factor but still something to consider)
= base cost
I usually knock off the studio fees and kiln costs, by make a selling small cost covers. Little objects that are easy to make and quick to purchase. They add up quick, fill open spaces in a kiln, and can be great ways to test new ideas too!
There are really many different ways of approaching. Check out Ceramics Arts Daily, they have great articles and forums with lots of help!
http://ceramicartsdaily.org/ceramic-arts-daily-site-search/?cx=001510309991982260494%3Afn9s4gctyhs&c...