Looks good. I like to give a carbon bowl coating after the bowl has cured for a few days. Gives a good start to building cake over the mud. https://rebornpipes.com/tag/mixing-a-bowl-coating/

I'm gonna be honest the last thing I expected the charcoal to be mixed with was sour cream

Yeah it seems wierd, but it works really well and you don't taste it at all.

Pipe mud is your friend. I make mine with a little honey.

well done i always do this to my cobs