A model of the Solar System containing 16 objects to true scale to one another made at the largest round number scale that doesn't require Jupiter to be split into different pieces .
The model includes:
the 4 rocky inner system planets
the 4 gas giants
the 4 Galilean Moons of Jupiter
As an added bonus the Gas Giants also feature their true oblate spheroid shape. Due to their rapid rotation, either Jupiter or Saturn and to a much lesser degree Uranus & Neptune are deformed around the equator, enough to be easily seen to be so with the naked eye.