See, all I want is a nice, angry mob of villagers, that walk out of their village (if you live close to one) and try to storm your house if they believe something bad is happening, e.g they see you brewing potions or you have weird things growing in your garden or maybe even because you stole of or killed one of them... It was be awesome.
But, if that doesn't happen, I would like to see maybe an increase in some mobs (passive or aggressive) like bats, goats (use horns to summon evil spirits or likewise), whales ( sell incredibly valuable ambergris to the villagers), mere-people and were-people/animals. Minecraft had its originality stem from its creativity, but they have kind of stopped adding in those weird, quirky things, like ghasts, zombie pigmen, slimes, and stuff.