Hi Steven,
Does the A7rIII do focus bracketing? the rII doesn’t and the Sony app is useless. Are you creating your stacks manually?
I’m using a turntable from orangemonkie called the Foldio360, so it’s semi automated and has been fantastic, though I probably can’t use it the same way, if I try stacking.
Your detail is great, but the dof is still too shallow, and yes, too much shine and reflection. Also try adding a circular polarising filter to your lens.