Late to the party but I also agree with all the above.
You say 'I have been trying to focus on one aspect of turning at a time. Initially tool use, then form and I feel the foot is next.' , in all honesty, I don't think there is much wrong with the foot, there is just enough to lift the shape of the form clear of the surface to give the impression of floating above the surface, something we all aspire to.
You may have taken the easy route by using the black pigment, but it certainly works very well against the colour of the Euc'.
Great form and even better finish.