If the camera is strictly an overview to observe what is going on, a 2nd story location is a great place and depending on the lay of your land, you can probably see more in the neighborhood that way. As long as someone realizes that they will not IDENTIFY at that location and have other cameras to do the IDENTIFY, it is a great vantage point.
A PTZ on the 2nd floor with its incredible zoom works well because it "flattens" the angle as you look further away, so someone 300 feet away will usually be a much better angle than the 1st floor that may have a bush or lamp post or car get in the way at the longer distances.
Now the downside is the closer they get to the PTZ, the more the top of the head you see, but if you have other cameras to capture them when they get that close, then a higher PTZ makes a lot of sense.