I think it might be weird. How about full length mirrors trimmed out with the sconces on the mirror equally spaced around sinks? This would have the benefit of giving a side reflection as well.

Also found a good corner tower pic:

Because of the different type of configuration you're doing, you're going to need more mirror than just over each sink. To me it sounds like you're going to need custom mirrors. I would decide on a shape based on the style of the home, and then I would create space over each vanity (not sink) for the same shape just a different size. And then determine your lighting after you figure out the mirror placement.

I don't know about your electrical wiring but I would do a small mirror over your husband's vanity with one pendant and a mirror twice the size (more or less) over yours and have two pendants.