Pluto and Xena are to the Kepler belt what Ceres and Vesta are to the Asteroid belt (the largest known bodies of those region). I can handle Pluto and Xena being called a planet as long as Ceres and Vesta are called planets.

I do not think the location of a Barycenter should determine whether a plane’s companion is a moon or a planet. The dominant body in such a system should always be the planet and the lesser should be the moon.

There are different types of planets. Jupiter is about as different from the Earth as the Earth is from Pluto.

I think we should have different classes of planets based on composition(density) and size. I have seen our solar system worlds (planets, moons, asteroids and Kepler belt objects) mapped out on a chart/graph where the y line is the composition (gas, ices, rocky, metallic) and the x line is the size. It works out really nice that way. If I can find the book it is in, I’ll scan it and post it.