Luis Castillo trade grades: White Sox get their guy without big return; how do Mariners use freed-up money?

The Seattle Mariners have traded starting pitcher Luis Castillo to the Chicago White Sox. In return, the Mariners receive reliever Seranthony Dominguez, outfielder Nolan Jones, and catching prospect Boston Smith. The deal raises questions about how Seattle will deploy the financial flexibility gained and whether the White Sox secured Castillo without giving up a significant return.