Well said. He was given command too quickly. Prime Kirk had to serve for sometime to get Captain. He was tested by the time he took the Enterprise. The Kelvin being destroyed must have changed the way Starfleet promotes. That's the only reason I can think why they would promote a cadet after one mission. A cadet that just days before was cheating on the Kobyashi Maru and arrogantly chided a bunch of Admirals and NuSpock about it was suddenly given the command of a Starship. I think we saw the results of NuStarfleet promoting NuKirk after one mission.
And then he was to be demoted. The only reason he ended up back in command was Marcus was sending him on a suicide mission. If I were to add in the conspiracy theory vibe then I would say Marcus was already Chief of Starfleet Operations and approved Kirk's promotion for his own purposes.
This is something that I have thought on in the past couple of days and have finally been able to put it down. It will be a bit long, but hopefully you'll read it all, everyone
First of all, Kirk's rapid promotion is not shown as being something we should automatically celebrate. His leadership qualities are there, but raw and requiring refinement. Personally, I think the fact that he was promoted at the end of 09 was a mistake, and that it should have either ended with a montage of Kirk receiving decoration after decoration and then being promoted to Captain, or serving as first officer under Pike.
That said, the idea that Kirk, as a cadet, can't be promoted is one that doesn't fit in with some of the other Star Trek works. I mean, Saavik is not treated as a cadet, but carries the rank of Lieutenant and is treated as a member of the crew and the chain of command. Red Squad's cadet leader was also field promoted by the Captain and made an acting officer. The results might not have been stellar, but it happened.
Cadets at Starfleet Academy don't seem to be treated like modern US Navy cadets. Instead, they appear to be able to be inserted into active duty as Starfleet (and the plot) needs. McCoy goes from a 3rd year cadet to chief medical officer, without seemingly a hiccup, and keeps his responsibilities. Saavik, similarly, also is placed on a ship at commissioned rank without any additional training or schooling.
Now, before the arguments start, yes, his rapid promotion to captain was too fast, but I also see it more in line with Marcus' plan to have a ship to use to start his war and a captain who would be easily persuaded to act rashly.
As an aside, Starfleet brass has not always had the best track record of making great decisions. TOS was a mixed bag as for every competent flag officer (Stone, Mendez) you have one that was incompetent, a paper pushing bureaucrat or inept. Even Admiral Kirk in TMP is a bit of a jerk to Captain Decker. If that story had happened in reverse, with Captain Kirk and Admiral Decker, Decker would be painted as more of an antagonist to our competent hero.
Finally, I agree that we saw the results of Kirk's promotion and the subsequent fallout. But, after he willingly sacrifices his life for his crew, what lesson would he learn being sent back to the Academy?