Bruce Greenwood has the distinction of playing the role of a Christopher Pike, who, in the Prime Timeline, is involved in a horrible accident and ends up spending the rest of his life on Talos IV. The Kelvin Timeline changed Pike's future, but Star Trek Into Darkness was a painful film for fans of Admiral Pike as his character was killed in a terrorist attack. Of course, Pike didn't return in the last Star Trek film to date, Star Trek Beyond, but there is a Star Trek 4 movie supposedly in the works. And in the 2015 edition of Star Trek Magazine, Greenwood expressed his desire to return to the character.
How would that be possible? Well, it's Star Trek. How many characters have returned after "dying?" There's even the possibility that Captain Kirk is still alive or will be able to be brought back. So Trek characters are ever really officially dead, especially if a storyline needs them.
Could Pike return to Star Trek 4? There's no doubt Greenwood would put on the uniform again, especially since he felt his character hadn't said everything that needed to be said to Chris Pine's Captain Kirk. He wanted to be able to tell Kirk that he was ready for whatever lay ahead of him.
"No, I think there’s room for more conversation, but that’s just my deep, deep wish to come back. On any level, I’m not willing to suggest the relationship is finished. It isn’t. There’s so much that drives the story as there’s so much left to be said between the two. You understand how much they care about each other, and you want to see that develop.Bruce Greenwood
You want to see Pike actually say, “Go well. You are ready,” but we never get there. "
Sometimes, though, it's best if the character is forced to learn on their own, without a mentor, and Kirk had to grow as a captain. He continued to learn in Star Trek Beyond, and maybe, if Star Trek 4 actually does get made, he will have reached the point where he doesn't need a mentor. But it would still be great to see Admiral Pike, if even in a flashback scene, telling him he'd done a good job and was proud of him.