The Abrams reboot left the Enterprise series alone (in theory anyways) so let's compare the original. Here's how the NX-01 looked like in combat
Note that the ship had generally poor weapons (torpedo launch rates were horrible). The Kelvin benefited from roughly 50 years of advances from this (2160ish to about 2213) but the Federation wasn't preparing for war either. You need to compare sizes of the various ships at this point (not embedding due to size). You'll note JJ Abrams giant sized his ship (more than twice the size of the original). Bigger... everything.
The eighth as I said is the new, larger re-imagined Constitution-class Enterprise from the JJ Abrams alternate universe "Star Trek" and "Into Darkness" (the increased size is due to encountering Nero's huge ship I believe).
This would make sense since the Narada was somewhere in the neighborhood of 8000m long. If you know there's a ship that big out there that's openly hostile towards you, you're going to build your ships bigger and badder. This is more or less confirmed in Into Darkness, where they're building them even bigger and badder than the Enterprise.
Torpedo launchers don't need to aim, per se. You're shooting guided missiles, essentially. My bet is that the Enterprise had faster torpedos. The NX-01 torpedos almost moved in slow motion. So, assuming that torpedo technology hasn't advanced all that much, you'd probably want to be able to aim them to give them less exposure to being blown up.