@ohtheurbanity This is a little silly, but I like the idea of zoning that allows buildings to grow another few storeys taller based on the buildings already there. Like, say, the maximum allowable height is the average height of the current buildings on the block plus one or two storeys.

Not locking developers to set number of stories is in my opinion good thing. In my country there are more important aspects to limit new buildings. Like how much shadow will new building cast to its surroundings (so people with sunny house/flat won't be in dark for the rest of their lives), flight corridors around airfields and more. It's not bulletproof but pushes developers and architects to think not only about the building itself but its relations to neighborhood as well. Also not having zones allows developers to create space for shops/services (usualy 1 or 2 floors on ground level) and rest of the building can be designed for housing.