Given how uh, liberal some of the interpretations of F5 damage were back then, I'm really surprised none of the Palm Sunday 1965 tornadoes was rated F5. There are a few that have better cases than some other tornadoes which were rated F5.Niles was by far the most violent tornado in Ohio history. Absolutely deserves the rating it was given, and produced much more violent damage than Xenia.
Also, speaking of other violent Ohio tornadoes, I believe that the Toledo. OH tornado of 1965 should have been rated F5. It swept away numerous anchor-bolted homes. The Pittsfield/Strongsville, OH tornado also may have produced F5 damage, though I haven't found any photographic evidence that proves this.