If we assume there are two universes that are identical until 2233, rather than that there is one universe that splits, we can debate the interesting point of "How identical is identical?".
That is, minor fluctuations might happen, and usually they wouldn't have a major effect. No matter how hard a butterfly flapped its wings, the MACO would be disbanded and the UFP founded and (against real-world odds but with plenty of Trek precedent) Sarek of Vulcan and eventually also George Kirk Sr born exactly as they were. But if enough of 'em blasted bugs did enough of that flapping, might the wormhole into which Edison so ineptly piloted his ship happen to lead to some place other than Altamid?
Regarding the wormhole, in ST:TMP we learn that warp engines themselves are one possible cause for the phenomenon. Perhaps the NX status of the Franklin (in the UFP Starfleet sense, not UESF sense) came from her still being involved in engine testing first and foremost, and this Warp Four veteran was now testing Warp Six engines and spectacularly failing? Making a ship go a hundred times faster than she used to would probably still count as a mission Edison would classify as "pushing the frontier" and being (falsely) upbeat about.
Timo Saloniemi
I suppose that admittedly makes sense - although one of 3 things are at play here..
1. The Kelvin incident caused a split in the original universe - meaning up until 2233 everything was identical because it the same universe until that point. This is the theory everyone seems to use at the moment.. That the Narada/Kelvin incident created an alternate timeline parallel to the Prime. With ST: Discovery being in Prime, I guess that is where canon is going as well.. Although it would be in between Kirk and Archer as far as the timeline goes from what we do know.
2. The Kelvin incident literally altered the future completely and there is no such thing as a Prime universe at all.. The blackhole that sent Nero to the Kelvin, and Spock-Prime as well would have been just like every other rift in space time.. The future is irrevocably changed and everything after Kirk in Prime has ceased to exist. (Side note - this would mean that STO and other works done after Nemesis other than ENT are moot - and void.. Which I wouldn't mind.. STO has overblown so much it is insane that it is considered canon...)
3. It is a different quantum reality (TNG: Parallels) Which would explain radically different ship designs, technological appearance - etc. Remember how things looked much different in this paradox of an episode.. There are unlimited amounts of universes if this theory is used - one that is ST Prime, the Kelvin, the Borg assimilated earth in another, perhaps in another Romulus won the E/R War, the Mirror Universe obviously, and others..
As for the Krall storyline - it is possible that it could have happened in Prime identically as in Kelvin, or being an unstable wormhole with unlimited quantum realities - it could have dumped the Franklin in the Delta Quadrant, or the Gamma Quadrant, or it could have sent it backwards in time to 5000 B.C... It is impossible to say.. The butterfly effect as you explained, would definitely be much larger with a wormhole - as it could have practically done almost anything with that ship. To guess it would have put it exactly on the same planet again is rather hard I suppose to imagine..
I don't believe in the Prime Universe.
Perhaps then you like either point 2 or 3 better than the rest? If this is the case, the TNG must be remade, from scratch.. As well as the rest of the stories.. With Kahn having been altered already drastically - it is possible prime will fade into oblivion and be remade into the kelvin timeline rather than alternate realities.
The Franklin struck me as a in solar system patrol ship, designed to help support Earth's efforts to colonize it's own solar system, while slowing branching out further and further outside the "neighborhood" as it were.
I guess it fits in with my idea of Earth Starfleet starting out like the "Solar Patrol" from Heinlein's "Space Cadet."
Then it wouldn't have needed warp drive for in system use... a waste of resources to give a ship FTL capabilities, if it is never going to leave the system. Remember in TNG - Best of Both Worlds - at impulse speeds they were able to travel from Jupiter to Earth incredibly fast.. So warp drive would be irrelevant and redundant. Maybe instead of a system patrol - it was a 'Core' patrol... Andoria, Vulcan, and other UFP core worlds would have been close enough for Warp 4 to reach comfortably if I remember correctly.