You can make one block equal 6 polys with displacement maps. Just make sure you have the block seams welded and do a UV map of the block. The white for the raised portions and black for the inset portions. 200 bricks=12000 polys or about one fancy dress for V4. It can be that simple,IMO.

I cannot save the world. Only my little piece of it. If we all act together, we can save the world.--Nelson Mandela
An  inconsistent hobgoblin is the fool of little minds
Taking "Just do it" to a whole new level!