idk y but i have the feeling Andrew Ryan will return because remember the vitachambers revive those with ryans genes. Maybe ryans was revived in a hidden chamber after we killed him in the first game?
its 10 years because a lil sister came back and was grown(i also speculate her to be the girl from the teaser trailer, and the first lil sister, just my thought). Remeber this 1st big daddy can use plasmids, maybe he was hiding out in bioshock 1, because we never saw him
no, remember there where many places in rapture we never got to explore, and theres no way we could have killed EVERY splicer
i earlier released a blog on N4G stating this. lol. after the first screens were released i could tell it looked better. because of how good ninja gaiden looked on xbox1, NGII wasnt as stunning. But sigma shows the real graphics of NGII