If Bellinger opts out the Cubs don’t have to move anyone to add a bat. And even if he doesn’t, they can move 9 guys around in 8 positions and add a bat. Catcher would be Amaya and whoever they add. If they can add a catcher with pop, that can also help. But I would be fine with signing someone like Kelly to share the catching with Amaya.
As for young guys ready to move up, maybe they go in a trade for that bat or they go for the best pitcher they can get in a trade.
The ideal off season for me would be adding one of Soto, Vlad or Tucker. Add a pitcher like Burnes, Snell, Fried, Flaherty, Gilbert or any of the other Seattle starters, or similar And trade for a catcher with pop or just sign someone like Kelly. Add a decent pen arm or two and call it an off season.
They wont have the money for all high end salaries, so if they did bring in one of the bats I am hoping for(and sign them long term) they might have to trade for a young arm and forget about the guys like Burnes. But that still leaves guys like Keller, Cabrera, several Seattle pitchers and even Crochett. I am sure there are a few more.