I chose this as one of the textbooks for our college astronomy class. It was excellent, and touched all four parts of the quadrivium (arithmetic, geometry, music, and astronomy), but more like an excellent workout rather than an excellent wrap up. Much of Kepler’s work was before his time, and above my head.
Published in 1618 Kepler didn’t even have the word “gravity” to work with as he tried to explain the movement of the planets. He did have theology, and the praise He gives to God throughout his work is a fantastic example of acknowledging the Creator while doing science.
Probably don’t read this one first in your astronomical aspirations.