I think length might also be determines by your own body build. If you have nicer legs, perhaps a slightly shorter length than if it is best to hide those calves.

I like my skirts to hit above the ankle, but I find that slightly shorter seems to look better.

A suggestion--make yourself several skirts in cheap fabric in the length you are considering and wear them a lot--do housework in them, practice going up stairs in them, and what happens is you will alter how you move a bit and that will translate into how you dance in a dress.