We could simply define Pluto as the edge of our Solar System and everything beyond its orbit a Kuiper Belt Object. There's nothing wrong with that.
Why bother coming up with a pseudo-scientific requirements list for planets when these don't work for a large number of cases.
That would include Ceres, Quaoar and Orcus as planets.
It's really hard to come up with a definition of a planet that includes Pluto but doesn't include Orcus. Orcus is very close to a mirror of Pluto that is 120 degrees out of phase. Even in name: Orcus is the Roman name for the Greek god Pluto.
What part of "we define it so" did you not understand?!
The three I listed are inside Pluto's orbit. Part of the time for the latter 2.
If you want to say that Pluto is a planet for historical reasons, that's fine. Just don't try to invent pseudo-scientific nonsense to justify it at the same time you are decrying psuedo-scientific nonsense.
> We could simply define Pluto as the edge of our Solar System and everything beyond its orbit a Kuiper Belt Object. There's nothing wrong with that.
There is because Pluto is inside the Kuiper Belt and just as much a part of it as all the other "planets" in there. There's nothing wrong with defining our solar system as having 8 planets plus a bunch of other stuff.
> We could simply define Pluto as the edge of our Solar System and everything beyond its orbit a Kuiper Belt Object.
A Kuiper Belt Object not being a part of Solar System doesn't make any sense. A star system is the star + all objects that orbit it. Why would you arbitrarily exclude some objects that orbit the Sun?