You better get down from that high horse of yours, and accept it: The balance should be based on everyone's data/opinion, since everybody who plays this game, payed for it, and bought it!
See, this is where you're horribly wrong.
Balance is not based on opinions and definitely not on opinions of lesser players, we can discuss balance all we want and that is why we are here on this boards, but about 99% of this feedback here is, well, worthless.
Balance is based on complicated relations between game mechanics, units performance, army concept, its performance alone and in team games against usual opposition, the popularity of units or the lack of it, but it most certainly isn't based on anyone's opinions.
We can judge the balance by the prism of our own experience in the game, the better we are, the more accurate insight we -might- have.
Why only might?
Because even top players can say utter bs at times and be biased, opinions are always subjective.
You can have your own, but it won't be as important as one of Luvnest or Jove for example.
"But, but the top 250 player know how to play...." yeah, 1/20 of the playerbase... Why does relic want to favour a minority of the playerbase?
Putting in another perspective: A car factory should manufacture only racecars, because the 250 racecar pilot around the world knows how to drive it properly... sounds like fun to the rest of the world...
Because that is how it works, always did and always will.
You create balance with competitive players and high level play in mind, because these players know the game, know the mechanics and can use them to their benefits. Low skill players often don't see certain unit relations or even map details that make a difference, not to mention lack the micro and awareness level needed in competitive play, issues they often accuse balance of come from their own lack of ability.
You don't balance competitive multiplayer games around players who can't play the game effectively, otherwise you wouldn't have "skill shot" abilities in mobas and competitive FPS games like CS would have aim assist.
If we considered balance for the amount of people playing, instead of the skilled top, blobs would be considered high level, micro intensive play.