Great idea, but just for people's information, I read that a perch should not be added to a bird house. Cavity nesters don't need them and it just provides a place for house sparrows to sit and harass the inhabitants.

I usually don't put one on and no one seems to mind

Yes, the birds come and go fine without them.

I really like your flower pot idea. Maybe I'll give that a try next spring. It would be fun to see what would use them. Robins tried some really odd places this spring, even using rotted out fence posts along the road.