Just some depth into the cubes of the heel and its perfect!

Hi! Feet are definitely hard. What you could try is to draw them as boxes first and then carve them out. It works especially good with platform shoes like this. Don't forget that heels are also sort of boxes and have multiple planes. Another thing: feet can't twist much and always follow direction of the knee. I would suggest checking leg lengths again because they see to be very different. Hope it helps. Cheers!