That works. The CVs are in a separate fleet with their own escorts, so they won't "steal" the escorts from the BBs and leave them hanging out front unsupported. The CVL provides air coverage to protect the SAG against enemy air attacks. There are enough escorts to cover the capital ships in case one or two get sunk. That all makes a whole lot of sense to me.
My only experience with Japan involved using the starting BBs plus one more in the queue, and focusing on carriers from then on. The old BBs are more than sufficient against Nat China, and can still do shore bombardment or break up an invasion fleet pretty well even with obsolete techs. Basically, I use the BBs as damage sponges, to pin the opponent in combat while my CAGs and land-based NAV and INT (or FTR) tear them up. Anything the BBs do on their own is a bonus. When you face the Royal Navy or the US Navy, you'll definitely want carriers as your main offensive arm.
My only experience with Japan involved using the starting BBs plus one more in the queue, and focusing on carriers from then on. The old BBs are more than sufficient against Nat China, and can still do shore bombardment or break up an invasion fleet pretty well even with obsolete techs. Basically, I use the BBs as damage sponges, to pin the opponent in combat while my CAGs and land-based NAV and INT (or FTR) tear them up. Anything the BBs do on their own is a bonus. When you face the Royal Navy or the US Navy, you'll definitely want carriers as your main offensive arm.