I love Mega Rayquaza because it means with almost 100% certainty that we won't get Delta Emerald (thank God). :P
Also, are we really classifying Megas based on what "needs" them? Who cares what "needs" or "deserves" Megas, I definitely love the fact that Mewtwo got two and I think Rayquaza could have two too. Also, Kangaskhan was definitely one of the Pokémon that "needed" a Mega and got one, and guess what, it's broken, so no one wants to play against it. Be careful what you wish for... :P And remember GF isn't a Pokémon charity house that only helps the "weak" Pokémon. Some Pokémon would remain weak even with Megas. I heard Mega Ampharos was UU and, while UU Pokémon are definitely not weak (they once were but not anymore with the existence of lower tiers), it's certainly underwhelming that a Mega is UU.