Either that or colour code them by function.I'm assuming you'll be doing shadows on the buildings later?
Torg's comment about not doing each building individually got me thinking.
I exported a bunch of buildings from the city generator and then pasted them in irregular groups along the lines of the road. The drop shadow on the layer works a treat.
Now I'll probably set up a square brush and make a second layer for 2 and 3 story buildings on top of the first.
I hope the spice the mix up with some notable buildings, palaces, keeps etc... Its just that for cities with 500+ homes you need to be able to automate some of the filler buildings.
Thats the method I see now anyway.... I'm looking for other options....
I'm guestimating 350 homes\buildings so far. That sound good?
Sigurd
Edit - Here's the same picture with highlights on the north west. It adds interest but they all sort of look like monopoly hotels....