3-9x is probably overkill, and you can get away with a smaller objective and less magnification for the same or similar light transmission you'd get from higher magnification and a bigger objective.

One thing though, illumination is something you're going to pay for that's going to detract from other areas. For example, rather than paying $400 for the best glass and build quality, you're paying for $300 worth of glass and $100 worth of illumination, for example. Not saying you shouldn't do it, it's your gun and you know what you want, but it is something to consider.