I think it depends on whether you want to make it a rectangular runner or a square table topper.
If I was going to make a runner then I would make another turkey and face it in the opposite direction with some not too busy fabric/pattern in between. The turkeys could be on the ends or midway to the end.
If I was going to make a square topper I would just add some borders of not busy fabric. Probably 2-3 borders of varying sizes to get it as big as I wanted it.
In any event I love the turkey and you did a superb job on it!