Completely agree. This idea of prospects coming up and filling spots is just not realistic. Sure you need a few guys to come up and be successful. But for a team like the Cubs, a high revenue team, they need a balance of quality major league ballplayers and some young talent sprinkled in. The idea of beinging up all the young guys or leaving openings for all the young guys is great for lower revenue teams who have no other choice.
If the Cubs did trade PCA+ for Luzardo or someone like that, and then signed Bellinger that would be great use of a prospect. You fill a need on the major league team. They have many guys who would be top 10 prospects in other organizations who are 15-30 on the Cubs. They could use those as well as guys like Wesneski,, Assad, and even Wicks to trade for guys like Naylor, Bieber, Lowe, Torres, Polanco, Alonso, etc…. I realize in this list some guys may not be available and some might cost a bit more (maybe a top 10 guy).
But they can fill 2 bats, 2 starting pitcher, and a pen arm with FA spending and deals. And still have a decent farm system. They would still have most of their top 10.
That is the way a major revenue team should use their money and assets.