You fill in the gaps with big money with players who are deserving of big money based on Scouting, development, future performance, positional performance and projection, past performance and consistency. That is why when you develop a Mookie Betts you don't trade the Player because you cap strapped your payroll with player signings like a Sandoval, Pedroia, Price and a Schwarber type player.
You cannot hand out guys like Schwarber 15 million a year because the market dictates it. Scouting and future performance and projection has a lot to do with contracts and what your going to pay. The big word here is consistency. Betts over a 7 year stretch had consistency year in and year out. Schwarber does not. Its one good year one not so good that is why stats at times are flawed. Yes schwarber has an .800 career ops but the model of consistency is a red flag!