About the 1x1 houses. There is a population min that must be reached (I've read 1100 sims) before the 1x1 lots will be used. Basically, to jump start the process, you need a few 1x2 lots to start off with. If you build a lot of comunities, you will end up with enough 1x2 lots, and then it just jumps - OR, you can build a line or two of 1x2 lots. I don't know if this causes problems later on with wealthy residential though - you may have to dezone the 1x2 lots.