The “ballast issue” referred to in the Wiki article was on the destroyer classes (Sims class was the last) preceding the Fletcher. The Fletchers and Gearings had flush decks and wider beams, eliminating the roll issues of the older cans. The problem with flush decks is they didn’t have portholes which made for lousy ventilation in the tropics. The design was so good that they lasted well into the seventies whereas the Sims and her ilk were all retired by 1946. Gearing design was so successful that they underwent FRAM I and II modernization, the last being the addition of a helo deck and hanger!
I thought this quote from the Wikipedia article was interesting: "after World War II ended, many were sold to the very countries they had fought against: Italy, Germany, and Japan, as well as other navies, where they would go on to have even longer, distinguished careers."