If your problem is that the uppers are too tight you may have to forget about minimalist shoes. They still haven't figured out that minimalist doesn't just equal a flimsy sole. It MUST also include a generous toebox. And wide sizes for women. Until they figure that out, I wear sandals. That's the only way to have truly generous space for your toes.
I have some Vibrams but I nearly burned my feet on the rubber running track the other day. Mine are a couple sizes too big to accommodate my pinky toes that are too fat to fit when the shoe is the correct size. They at least are wide enough. Every other minimalist shoe is way way too narrow.
Female, 5'3", 50, Starting weight: 163lbs. Current weight: 135 (more or less).
I can squat 192.5lbs, press 75lbs and deadlift 210lbs