A few suggestions from me include...
1. Vary the color of the roofs; reds, oranges, greys, some redder browns
2. For the roofs, also, never use black
3. The real houses vary in design and material, like one half may be stone while another might have a stucco finish-varying greys and brick sizes for stone and a range from light tan to dark tan
4. Plant growth on the sides of buildings is huge- this adds realism and a classic Italiano/romanic touch
5. Lambourgini-streight up I freakin serious, use the Turismo
6. Some people can't tell Italian architecture from other forms, so include major structures, such as the colesseum, pantheon, theaters, baths are still around, and forum
7. And if you wanted to reentact a battle scene from their roman past, then use striker150's roman decal pack
8. Tying back to colors, whites, tans, reds, greys are good colors for the walls.