Boyce predated Discovery and SNW; presumably M'Benga is his replacement. The second-pilot characters who could be developed more include Mitchell and Kelso as well as Piper. Although I don't think it's necessary to feature them all just because the original pilot did. TOS had plenty of officers who were in just one or two episodes and never again, like Riley and Palmer. Mitchell, yeah, since he's canonically established as Kirk's longtime friend who came with him from his first command. But Piper was such a nonentity that he could easily be skipped over. (Various novel and comics versions of Kirk's early days on the Enterprise, including mine, have brought in McCoy from the start and assumed Piper was just filling in for him temporarily.)
They're not doing Year One.
If they were doing Year One, McCoy and Sulu wouldn't be in SNW's final episode (Instead, they would've gone with people like Boyce or Piper -- people who can be developed into full characters).
Just ONE would have been enough.
The TOS crew has been done to death (We've just finished the Kelvin trilogy and its Young Kirk and Young McCoy.)
In theory, Year One should be the show I've always wanted. A full season before Where No Man, where the absolute TRAUMA of that episode would finally be fully realized.
- Gary as the emotional, snarking part of the Trio, before McCoy. Give him Ensign Riley to corrupt and prank lol. Really explore his friendship with Jim. Give him really good instincts, hinting at his latent Psi abilitiy.
- Keep Scotty in the engine room, getting it just the way he wants it, and let Lee Kelso be the hands on, Macgyver-like tech genius on landing parties. He and Gary are the show's Chekov/Sulu, a good friendship that makes the ending of it all that much harsher.
- Develop communications officer Lt. Alden.
- Slight retcon when Dehner eventually joins the crew, expanding her onboard time before Where No Man and giving her a history with Gary, who screwed her over ROYALLY. He's the womanizer Kirk is accused of being.
- Spock becoming more withdrawn and minimizing his human side, with all these changes and new people. He was younger, more raw and vulnerable with the old crew, and he's not letting that happen again, but is secretly enjoying the banter and sarcasm.
- Dr. Mark Piper, exhausted and burnt out with each and every casualty and bit of craziness that comes his way.
- Yeoman Smith - absolutely wide open character.
I am VERY GLAD they are not going to do Year One. I love the show I built in my head, that I have dabbled at fanfic with, to the point that whatever they actually did with the show, I would probably despise it. Lol.