The new Trek movie doesn't "destroy" the classic timeline, any more than the original series episode "Mirror, Mirror" and its DS9 followups (not to mention the TNG episode "Yesterday's Enterprise") destroyed it. We're merely seeing an alternate timeline, split off from the original by the Xindi War, then later by Nero's machinations.
And the Vulcans weren't all "killed off"; even in the original, it was pretty clearly implied that Vulcan had seeded a number of interstellar colonies, and Voyager baldly stated that Tuvok was born on a Vulcan colony world.
Yes, the new Enterprise is quite a bit bigger than the first one - heck, it's almost as big as the Galaxy-class 1701-D! That makes sense in the wake of the Xindi War, though, especially after the look they got at an Aquatic cruiser (the giant craft that brought NX-01 back to Earth in time to stop the Weapon). And it was built in Riverside, IA, rather than the San Francisco Shipyards, because of Nero's destruction of the Kelvin, which inadvertently turned George Kirk into a hero (in the original timeline, he lived at least into Jim Kirk's adulthood, and so far as we know was never a hero), and led to the honoring of his hometown.
I do wonder if, in this new world, George Samuel Kirk Jr (Jim's older brother) will still be fated to die at the tentacles of a flying jelly pancake... 
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Sodium is a metal that reacts explosively when exposed to water. Chlorine is a gas that'll kill you dead in moments. Together they make my fries taste good.