To be fair, we really haven't played a metagame with just sand and sun - Excadrill is far from broken so there would have been no need to ban sand and subsequently sun. People just automatically assumed this.
And if we are going to implement a Drizzle + pokemon ban, we sure as hell need to include Manaphy in that. Its these mini debates that make me think Drizzle should have been banned alone.
We have played a metagame with just Sand. Most of the battles at the top of the ladder were decided by a Doryuuzu speed tie. Admittedly, this was back when the metagame was still shaping up, but the point still stands.
Also, Sand nearly always beats Sun from my past experiences, largely because Ninetales can't switch in on any sand sweeper safely, and because it can't really do anything to harm Tyranitar.
And Unholy Confessions, I (and many others) have said it once and I'll say it again: Play the game, read Aldaron's proposal, and then come back here with your opinions on "banning Outrage + Garchomp."