Hi Joe. Thank you for your kind words as well. I definitely see a multitude of things that I will do differently in my future builds of rock/slab pottery.
This pot is large (for me) around 26x21" on the inside measurements. I've never measured the total length and width of the pots exterior, but you're looking at another 11-12" in width. The build of this pot involved 75 pounds of wet clay.
You're dead on...I started with a simple, rectangle pot. My original idea was to do like you said and build directly off the walls of the pot with slabs...this method didn't work out so well and was going to add even more weight to the finished pot. My solution to this was to basically build a double walled pot to cut down on weight, material and chances of cracking during drying and firing. I used a variety of tools to create the shaped of the rock form. Anything from pieces of wood, concrete and brushed were used to created the textures.