First, shown below, is the finished tutorial animation:
1) Naturally, the first change was adding correct textures to the planets:
Using textures from https://www.solarsystemscope.com/textures/, I applied real-world accurate texturing to each of the planets in our Solar System, and added an image background of stars. The rings of Saturn required adjustments to the UV Mapping.
2) I adjusted the initial orbits so that they did not all start in a line in the initial frame.
What isn't pictured, is that each of the orbit speeds were also adjusted to be correctly proportional to Earth's revolution speed. In the animation, Earth will do one revolution, and the planets will each orbit about the correct amount proportional to one Earth year. This was done to be more true to real life, and to add a little more variation in the animation rather than having the same initial positions and orbit speeds.
3) I created a point light source at the Sun, so that only the correct sides of each planet were lit.
Shown here is the Earth and Jupiter being lit by this new light source. As will be seen in the animation, every body in the Solar System will be only partly lit due to only being illuminated on the sun-facing side of the planet. What isn't captured particularly well in the image, is that a texture map for Earth at night is being used as Earth's texture's eminence so that when a side is not lit you can still see the light's of man-made structures.
Some small additional changes that were made that are not shown here were giving each moon textures, adjusting the size of each moon according to their real life proportion to their planet, adding some small orbital tilt, and adjusting planetary rotation to be more realistic (proportional to the revolution speed). Additionally, the sun rotates slightly to add a little extra motion to the animation and the camera zooms out from a close up on Earth.