Kevin, what size do you cut your blanks at? When you get one side cut, do you place it back into the void that was made from cutting it out? I do, and I always slide a small piece of veneer into the cut left from the blade. Plus, I tape the house into place, this holds the cutting in place while cutting the other side out. I find that if I don't do these two things, my ornaments don't turn out right. They seem to be a bit lopsided, or, a bit overcut in places leaving saw marks. It only takes a few seconds to do what I do to make these, and I'm more satisfied with the finished project. These birdhouses don't have to be made from hardwood, they can be made from softwood also. I suggest that you start out with softwood, then when you get used to making them use hardwood. I'm not to sure that you will like cutting these, they take time, you have to cut slower then usual. I'm sure that you can succeed at making them, just take your time doing so.
Len