I'm on the lowest pop server for NA and all large/medium houses were bought up preeeetty darn fast and I see people in PF asking to buy them on my server. So even if you move to a low pop, it doesn't really promise you anything except a better chance at getting the house.
Luckily, I was able to snag my dream plot (8/38) and my in-game hubby got 30/60. But we memorized our route, picked a ward we thought would be good and aimed for the subdivision, practiced the run, downloaded the patch 2 hours before the servers went live, logged in exactly the moment servers went up and gunned it for our plots.
Even though I got my house, I have to admit this is a broken system. Needs to be fixed. You shouldnt have to do all that I did and stress out about it for hours before the server goes live just to get a house.