I absolutely adore the main body, I like the box, and I do think you could have done better on your finial. The bottom quarter of the finial is OK, and the very top is a question of personal taste. However, the taper is, in my opinion, not good. It's way too thick.
This is a marvellous design. Splendid. The execution of the main body is close to perfection (well, in my opinion). And the box itself works. The finial turns a brilliant piece of wood turning into a very mediocre one. Please, do not get disheartened over these harsh words. I am trying to say to you: you made such a beautiful thing, why did you not finish it with a beautiful finial? Clearly you have the skill to do it.
But let's hear what others have to say.