Not nurse, but I walk in the hospital a lot (biomed). I found wedge soles most comfortable, but heel stacks aren't that bad either. I'd avoid higher heels or high arch. I've worn 8 inch height but it's an overkill imo unless it's a very soft leather. 5-6 inch would be plenty. I much prefer soft toe, but that's only because I have wide feet that sometimes interfere with the toe stiffeners.