Beautiful piece of wood.
Simple but effective form/shape, I know when it comes to hollowing some people like to stop in the "safe" zone (thickness) but I believe, you could have went a lot further, if you have the right tools and the nerve for it.
Spalted woods untreated are generally quite soft to turn and thinned walled pieces are very difficult to obtain but when the wood can be stabilised, you can go as far as you want, considering that you have the tools and the skill to it.
I'm trying to give you constructive criticism and I'm willing to talk to you a little further if you feel that you could get some advice on achieving thin wall hollowings.
However, if is the pic that is giving me the illusion of thick wall (belly), I apologise for my observations...!
Cheers
George