i'd lower the car first with whatever sort of suspension you want in the end... just springs, or coilovers, or adjustable coilovers...
that in turn determines what kind of wheels/tires you can get. there are more choices in size in the wheels/tires than there are with suspension height (unless you go with the adjustables of course)
and of course, research and knowing what you want is key.
however, if you want a particular wheel/tire combo, you'd have to find a suspension setup that would accomodate the wheel/tire and look good on the car (ie: not too much of a fender gap).....