No, it should have been a straight up prequel in the prime timeline with no " Old Spock "( not that I didn't enjoy him or the movie) and no Romulans.( not that I didn't like them either) If I had my way, I would have focused on young Kirk and young Spock much like they did in the movie. then movie to the Academy and a longer Kobyoshi Maru scene. Have Mcoy come in while Kirk is at the academy, then end with Kirk and Spock and Mcoy save the day and Kirk and crew ending up on the enterprise some years later. You could have that spread over two or three movies much like SW prequels, but spend very little time with boy Kirk. Make Pike the hero in the first one and establish friendships and everyone gets assigned to different ships. The second one a huge threat comes about that involves multiple ships: Enterprise, Faragout, The Bad guys. The third movie caries over from the second( POTC style ) and involves the bad guys still on the run and like I said Kirk saves the day and in the very end we see Kirk assigned to the Enterprise after Pike is incompcitated. No " canon violation" and all is conected together. The gaps are filled. I would update the tech a little and make it look like a mix between Enterprise and the Kelvin, the TOS look would be updated, but recognizeable.
I posted a similar synopsis covering key events leading up to WNMHGB many months back... I frankly wouldn't have minded Nimoy appearing somewhere in that kind of film series, teaching a class of Vulcan & Romulan kids about his history. In terms of a traditional prequel, that reverse narrative would only work as the final part of a trilogy... once audiences have already seen most of the crew's origins and are too invested in the characters, waiting for the final piece of the puzzle, not caring when it's revealed that Spock lives to a ripe old age.
By the closing chapter, there's even a "get out of jail" card to hand purists about the changed look of TOS... since the memory cheats even for a Vulcan. Or one diagnosed in an early stage of Bandai syndrome at any rate... So the point would be the story remained the same, just the finer details ended up exaggerated in Spock's mind.
Okay maybe it's a little Life On Mars
, in that we're seeing a fantasy created in some guy's mind... but that didn't stop Ashes to Ashes
continuing with those exact same characters in the past. Only with this you're blurring an established point in Star Trek's history and by adding a storyteller in the final movie, using Spock's fragile health to justify whatever changes are made. Or at least confusing the audience so much that they don't care and just accept it.
That end result is sort of where the writers hoped I'd be right now... only inventing some weird hybrid of time travel and alternate universe, in order to excuse how they just fancied altering almost everything... didn't quite achieve that.