Why? Any character should be understood enough, no matter you use 1 for each movie or just one guy through all three. And no, Dooku already showed up in the trailer, certainly they weren't trying to hide him like Talia in TDKR or Killian in IM3. He was not something like GG, GG had the chip in his mind to command all the droids. Maul, didn't have such skill, nor was he a military commander. Even in TCW, he won simply because both Satine and Vizsla aren't smart, especially Vizsla, who chose to duel him. I already explained. No, nobody said Leia or Han shouldn't get more development, but OT was not THAT badly affected like PT due to many reasons, and this is not a thread about Leia or Han.