So I have seen it three times so far, and after being slightly underwhelmed by it after the first viewing, I really really loved it after the second two viewings. I gave it an A-. It was such a nice blend of the past and present of this franchise. The new and old characters all worked really well, and I personally like Krall and his twisty backstory. The effects work was also great (minus that really strange intro shot of Kirk and Jaylah on the bike, that was odd looking.)
A few things I would have like to have seen, and a couple of theories.
As for the Enterprise's crew compliment, perhaps she wasn't fully staffed when she went to Altamid. It seemed like the crew was supposed to have some R+R on Yorktown, so perhaps she was sent to Altamid with just her operations crew, without all the scientific and research teams. I mean, it was supposed to be a quick rescue mission for the ship, so it would make sense to leave any extra people behind at Yorktown. If she had a crew compliment of 1200 ish, maybe she went to Altamid with only a couple hundred onboard. It would sit well with me to think that the majority of the crew wasn't massacred in the battle.
Also, I wish there was some explanation about why the transporter wasn't used to go after Krall at the end. Just some throwaway like about how the systems were offline due two the Swarm attack on the base.
I gotta go see it again.