The idea behind these two was duality.
White and light colours VS Black and darker colours.
Stonework designed like a sun, with growing sprouting vegetation in the spring VS grey rocks like the moon, with dying vegetation in fall/winter.
Young Jedi knight VS old Jedi master.
Like with other pieces, I also specifically wanted to avoid the main characters in the movies as much as possible. Obviously, this wasn't possible, or desired, when it came to Palpatine or Vader, since they are at the pinnacle of the Imperial power structure. But, it was possible with the Rebel queen and king, since they are minor characters in the movie, but major players in terms of political power and influence for the Rebellion.
That being said, for the Jedi master (Rahm Kota and/or Kanan), the duality aspect also gave me the added feeling and connection to how Luke Skywalker began dressing once reaching Knighthood after Yoda dies and his lightsaber construction in the Tatooine cave (ie - black/dark clothes).
Also, another connection I forgot to mention was the Imperial rooks and knights to the Rebel rooks. My decisions for those pieces' characters stemmed from choosing first the Rebel Fleet Trooper as the basis for the Rebel Rook. I then took artistic license in creating a Rebel High Command Trooper with the green/khaki colour. Then, I decided to use ROTJ's Death Star Trooper for Junior-grade Imperial Officer uniforms in Navy-black and Army-brown, just so I could match the Rebel rook helmets with an Imperial helmet that was visually similar (ie big and goofy). After that, it was easy to decide to have Field-grade Imperial Officers with Army-green and Navy-grey uniforms as Knights, replacing the Jedi Order, while the Rebel side still has Jedi Knights as chess knights.
