I guess to advertise Infinite. But Big Daddy is the most recognizable Bioshock character so it makes sense to have him as playable. It is weird though, I wish Rapture was the invasion instead of Columbia again.
I think it'd have been cool if Elizabeth was a playable character, and that's totally not because my best friend's friend voices her in the game. Lol. I think she'd have a cool move set, but I guess that's what DLC is for.
Still, Big Daddy is very iconic, and instantly recognizable, as I remember Bioshock being one of the big new titles of this generation, along with Gears of War and Mass Effect. Basically, those three were the poster children for Unreal Engine 3 for the longest time.
EDIT: at SAB, I totally understand where you're coming from, but I don't think 9 supers at a player's disposal would ruin their niche. Looking at the mock Kratos expanded supers (6 additional supers), they don't do anything that takes away from his niche as a mid to close range brawler. I even kept his Typhon's Bane Super as a mid range attack, so he's not stepping on Radec's toes, or any other long range character. I'm thinking more along the lines of the entire roster, as opposed to the 6 player roster in the beta, which, sure, if only those 6 characters were present in the game, I can see how there could be some overlap as far as niches. But having played the final code of the game, with all 20 characters, and I've fought against just about everyone in that roster, I don't think an expanded Super system would hurt anything. It's just giving more options to the player, and opening up more strategy to make it just that much more complex and deeper of a fighter.
The game works on two levels, as a straight forward, 4 player brawler, and secondly, as a more tactical, strategic, almost "traditional" fighter. Expanded Supers cater to the latter, while the former can still play it straight. Also, these are ideas for a sequel, and I would have it be just one more optional setting in the game's options. If you want to play "Classic All Stars," you can, but if you want, you can play the newer style, with the extra supers. I'm curious to see what PBR will evolve into as far as Sequels go. This first attempt is already fuck awesome.
I've definitely decided to main Ratchet instead of Kratos in the final game. I'm surprised at how much Ratchet fit my playstyle better than Kratos does.
EDIT: @ Chuck, that could be really cool too. That would really open up the moveset like crazy. Lol.