I know exactly how Spock took it
Well your comments in this thread indicate that you don't.
seeing ones planet be destroyed is several orders of magnitude worse than seeing ones best friend die.
Ever heard of the expression "the straw that broke the camel's back" ?
Well ST: Into Darkness is a steaming pile of boiling emotions, illogical actions and threadbare plots.
So it's realistic, then.
It doesn't explain too well about Admiral Marcus' reasons for becoming this dictator, so he wants a war fine.
Sure it does. We've discussed that at length.
Spock is way too emotional.
By what metric ?
I know TOS Kirk broke the rules from time to time, but those were under exceptional circumstances, yet Into Darkness just portrays Kirk as this hothead who recoils at following orders.
You might have missed it in the first movie, but he had a very, very different childhood from Prime Kirk.
Kahn was good, but boy did he make some dumb decisions!
Then I'll say this for him, he's consistent.
Hell Odo didn't cry once, but you could always tell when that character was in pain. But no, NuTrek Spock is illogically emotional.
Yeah but we're talking about Odo, here.

Vulcans have much more violent emotions than humans.
Didn't humans attack those Klingons on Qo'noS?
How would the Klingons know Starfleet was even there ? Plausible deniability.
Right now Star Trek has become like Star Wars
Oh, I wish people would stop making that parallel. The new Trek movies are NOTHING like Star Wars. Action doesn't equal Star Wars.
and the franchise is going to wither away and die because of that.
Actually it almost withered away and died for the reverse reason.
Lastly Into Darkness felt like a very watered-down version of Star Trek.
It felt like TOS, actually. Quite a bit.
This is not reinventing Star Trek, instead this is killing the franchise
Please do not confuse your appreciation for a movie with its level of success. The box office revenues disagree with you.
And finally two more points: Starfleet feels too much like an army and those caps really suck!
Starfleet has always felt like the military, and they've had caps before. They just never wore them. Hell, there was one in the very first pilot.