Elvis moved in about two weeks back, and he place his house RIGHT in front of my bridge and smack in the middle of my planned path area. :/ and I couldn't plot reset because I selected my Mayor. Wasn't expecting anyone to move in. >_<
I think it can be frustrating at times and it will definitely save you grief if we could just pick but I always picture the villager running around town like we did and picking their house (and defying the logic of paths :3) I usually wait until I get everyone plotted before adding paths and if I move someone out, I try to get the newcomer around the same spot as the villager who moved out. Hopefully the next AC will have a better system with the villagers choosing their house locations.