Some of what you're saying conflicts with the established years mentioned above. Also, have NO idea why you're saying the Talos mission "may not happen".
The original pilot, the cage takes place in 2254 (also the same year ENS. James T. Kirk graduated from academy in the original timeline). Since the Enterprise had not been built yet in this timeline, the events cannot take place as they did. Pike may have been involved in command of another ship or another ship with another crew may have gone to Talos IV.
Pine is 28. The one thing that really can't be changed by Nero is Kirk's birth year of 2233.Why do you say Enterprise is built with Kirk in his late 20s or early 30s? Is Pine that old? Is he playing Kirk that old in the motorcycle scene?
For one thing, I suggest above the possble launch dates (with Pike as Captain) as somewhere between 2252 and 2256.
This leaves open the Talos mission date. Besides, if Enterprise launched with Pike in 2256, they could still end up visiting Talos IV.
As for Pine being 28, there's nothing that says Kirk is 28 when he's watching the Enterprise being built while on the motorcycle. He could be a few years younger.
Kirk is still a cadet when he comes aboard Enterprise in the altered timeline and that the main plot takes place at that time. Greenwood's Pike is also about a decade older than Jeffery Hunter's. The kicker is Chekov, if the events took place in the 2250s he would be around 10.