Unexpected new additions
The passing of Anton Yelchin is a big blow to the film franchise and could be a problem moving forward. With tragedy, however, can come an opportunity. If you have to replace Yelchin’s Pavel Chekov, don’t. At least not with another Chekov. The best bet is to go get Alice Eve, Sofia Boutella, and maybe even Tyler Perry to come on in starring roles for the new film.
Alice Eve is an amazing actress and her turn of Carol Marcus was well received, even if not everyone loved the “bikini scene”. She was engaging, dynamic, and captivating with her performance, and with Marcus’ tie in with James T. Kirk in the original universe, the character has plenty of organic storylines to explore in the Kelvin universe.
Boutella’s turn as Jaylah and the character’s overall design was one of the best parts of Star Trek: Beyond. Boutella is one of the more impressive actresses going in Hollywood and her place with the first Kingsman and Trek franchise has made her one of the more popular sci-fi actresses.
Jaylah could be the new replacement for the departed Yelchin/Chekov on the ship’s bridge or could be an unofficial member of the crew. Maybe she’s the reason the film happens, as she’s been taken captive or has started an intergalactic incident. The possibilities are endless.
There’s also the idea of bringing back Perry to the franchise as well. With so many authority figures dying in the Kelvin timeline (Kirk’s dad, Captain Pike, Robocop), having someone that knows Kirk and his behavior, attempting to hinder or help him would be a nice wrinkle into the fourth film. It all depends on how you want the character to be portrayed.
There’s also the possibility of bringing original series character Gary Mitchell to the franchise or incorporating a character like Number One for a film version. While in cannon she came to the Enterprise first, under Pike, who’s to say that in the Kelvin franchise she doesn’t come back? The fourth film could be about how Starfleet has lost its faith in Kirk and crew and put Number One on the ship to determine if Kirk should be removed from his post.
There are possibilities that you can go with for replacing Yelchin’s role, and a combination of the ideas listed above may bring enough excitement to the franchise to warrant a strong fan response.