Hi!
It sounds as if your shoes may have been a bit too big from the beginning, or the materials used by Capezio have way too much give. Just a thought for when you do actually get new shoes.
In the meantime, if you've already tightened the straps and have the heel inserts, the only other things I can think of suggesting are wearing those little foot socks. I'm not sure if you are referring to latin shoes or ballroom shoes, and this will only work for ballroom shoes. You can get these little socks almost anywhere that sells pantyhose. They're just socks that only come up to your ankle, but are low cut in the front. They are designed to be worn with women's dress shoes. These might take up some of the slack and won't be visible.
The other thing you might do, for either latin or ballroom shoes, is get a bunch of those clear straps that Ladydance was talking about and used them to strap your foot in. If your shoes are really that big, you'll need a few.
I wish I had something more useful to offer, but really, once your shoes stretch out that much, the best solution is to just get new ones...which is not always possible right away. I hope this helps, and if not, hopefully someone else will have some creative solutions for you. Good luck!
-Lorena
