The whole concept of this article is just inane. Cleveland had little room to improve. Let's say they could go from a 1 to a 1 seed as one way to measure it. No room. A lottery team that goes to a 6 seed has improved far more dramatically.
If you are trying to say that Team x did the most to get themselves into the championship favorite position, that's one thing, but that doesn't really mean "most improved" as much as it means most likely to have solved last little needs to get over the hump.