Change 1: Scale

I adjusted the size of the Sun, planets, and moons to be as accurate to scale as possible, based on data from NASA's website.

The exceptions are Mars's moons, Neptune's smaller moon, and Pluto's moons, which would have been too small to be at all visible if sized exactly to scale; these all had their sizes set to 0.015 to make them consistently visible.

Change 2: Textures

I added images of the actual planets' surfaces (courtesy of Solar System Scope) to use instead of the solid placeholder colors. For my own sanity, I used the same texture for all moons.

Change 3: Orbital Speeds

I adjusted the speed of the planets' orbits according to the actual planets orbital speeds, giving Pluto the slowest orbit and Mercury the fastest.