It doesn't just boil down to the endgame of "one set being the best"; it's about having options, sinking time into theory crafting, discovery, and all of the fun that goes along with that. Personally I'd have a lot of fun experimenting with different sets and playstyles, and I know a lot of people that would as well. Yes, there will be certain sets that are the result of 100th percentile number crunching but at the end of the day that level of optimization is not cared for by a majority of players while things like how a class plays and feels is. Giving players more choices to compliment their playstyle would be nice.