Dragonite, Tyranitar, Salamence, Metagross, Garchomp, Hydreigon, and the gen 6 pseudo should all get megas to maintain their dominance as the top dogs besides legendaries. With the rise of new megas, the pseudo legendaries won't be nearly as powerful by comparison. Now starters will rival the power of pseudos, along with common pokemon like Ampharos and Absol.
Without mega evolutions, the pseudos may even become outclassed, and their prestige will turn to crap. I know some may think that mega pseudos will be OP, but GF can just make the megas have enhanced abilites, more favorable typings, or only slight boosts in certain stats.
I agree that the pseudo legendary (and the legendary) are the last pokemon that should get mega forms. Admittedly, those that want the uber powerful pokemon will like them, but giving the less overpowering pokemon a new perk would only make things more interesting and varied in battle. Weather teams are overpowering as it is and giving Ttar a boost would annoy me. I also like scizor, though it is on almost every OU team as it is.
I do have to say though, I am excited to see what mega gengar will be (assuming the new rumor is true). --- Standard OU. Only released dream world. White: 3997 6118 8758