I would LOVE a smaller one. And in the summer that is what they have. But I haven't found a smaller heated one. Grrrr.You probably won't like this but have you considered getting a smaller one that is lighter/less cumbersome to flip?
Like this
Or a fill from the top one? (i.e. nipple waterer)
Like this one
And yes - the nipple waterer would be an option. They have a nipple waterer on a heated base inside the coop already, so I could just abandon the hanging waterer in the winter altogeher and let them deal with the nipple one.
But I am a softy - and they clearly prefer the open one (though they are perfectly adept at using the nipples).
Maybe I just need to practice more - the second time today (after I washed the floor of the servants' quarters in the Chicken Palace) I was clearly already a bit better at it!