I don't think any fighter in their right mind would be keen on being a big fish in a small pond. More importantly they would be doing a disservice to themselves.
Me personally, I would rather be challenged in the best org than settling for something mediocre. To me thats like trying to master a video game in sp on the easiest difficulty and wondering why you suck when you go online against actual players. You're not doing yourself any favors.
Best Fighter on the planet.