Apart from Earth, I like Mars and Venus the most. Both are Earth's "siblings" so to speak, as Venus has a comparable size to Earth, but lacks the criteria to become habitable, like being in the habitable zone, and might even have been habitable once.
Mars not only looks nice, but is also the best candidate for human colonization in the solar system, as the planet is very close to Earth and just needs a shove in the right direction to become inhabitable.
Also, Mars has a mountain with the most badass name one could imagine: Olympus Mons.
I like Pluto as well, because fuck you, Pluto is still a planet in my heart.