I have some more hopes;
What about... a Fearow evolution? When I first saw Braviary's silhouette in the early days of BW leakage, I was convinced we had finally got a Fearow evolution. It had similar wings, a distinct head crest, and a beak that looked remarkably like an Andean condor. It looked big, it looked majestic, and thinking about it, I realized that Fearow really deserved an evolution, imo. The idea had not touched me before, but after I first saw that silhouette, even when Braviary was revealed, it wouldn't leave my mind.
Or, maybe Beheeyem? I think GameFreak is more likely to release evolutions to recent Pokémon than old ones. They want to cater to the kids who grew up with and learned to love Pokémon from D/P and B/W, and the earlier generations have already had their share of evolutions. In that respect, we look to the oft-overlooked, yet memetastic Alien Pokémon. Its current Base 125 Sp.A is nothing to scoff at, and with an evolution it would be rather devastating. Well, maybe someone might think that would be over powered, keep in mind that Rhydon had base 130 Atk, yet it received an evolution nonetheless (as did Kadabra and Magneton, both with base Sp.A of 120). A Beheeyem evolution would also be a late-game Pokémon, seeing as it evolves from Elgyem at lvl 42.