Classic Plus also provided a 50% bonus in miles.

Also, it was 100% refundable. From the other thread, the Works is a fee where the fee itself isn't refundable.

With Classic Plus, I used to find that I couldn't request a full refund unless I called by phone. It wasn't as slick as using southwest.com. Often at times, it was priced more than 2-3x that of the economy fare, when economy fare was low. But other times, it could be less than 2x, and then worth it for the seat selection, bag and 50% miles bonus.