I basically like the IAU definition, with the below exceptions:
1. there would be no "dwarf planets" only Mercury-Neptune 8 planets
2. Pluto and Eris would be Kuiper Belt Objects. This is clearly indicative of their kinship with each other, they must have formed at a similar time and location in solar system.
3. Ceres would remain an asteroid because it was formed in the same fashion as other asteroids in the asteroid belt.

Classification makes more sense to me when objects are grouped into groups of objects who share a common history/location of formation. The real planets do have this in common: they all swept their environments free of most of debris and are unique in this regard.

Currently, IAU has non-related objects like Ceres and Pluto grouped as "dwarf planets". they have no history in common, but do have history in common with the KBOs and Asteroid belt.