Fast Way of Drawing Walls in a House?

I don't find 'drawing' walls slow or inconvenient. The tracker, drag, drag & copy and marquee commands make things all very simple. I dont see how using zones and magic wand would be quicker - design the walls the way they need to be then magic wand the zones or slabs. I find the design process is a piecemeal approach (I do initial sketches by hand anyway to start off with) and I like being able to get all walls in position adjusting and modifying as I go before I add other elements. How can you add a zone if you don't know what the final room size will be? You would be constantly readjusting the size of the zone or you would find yourself adjusting both the zone and the walls which is making more work. Also I work with complex profiles and the external walls can't be just magic wanded to the slab as the slab is smaller than the actual building perimeter and aligns with the internal seperator lines one of the skins of my complex wall. Also if the external walls have to be sized for a modular building product (bricks in my case) its better to start with those first anyway.