FanFicRecs Iaculus' review
This fic is littered with Rouge Angles Of Satin, has a plot that is outpaced by glaciers, and has an update schedule that makes even that look speedy. None of this, astonishingly, prevents it from being heartwarming, hilarious, and really rather lovely. Highly recommended, but even with the promise of new chapters to come, don't expect a conclusion any time soon.
FanFicRecs Sporkaganza's review
This is an excellent fic and definitely worth your time, but there are a few problems. Shinji's sudden acquisition of Deadpan Snarker powers can occasionally be grating, the Asuka/Shinji shipping in later chapters can be a bit much at times, and Gendo is painfully close to a Complete Monster. Still worth a look, but just something to keep in mind.
FanFicRecs Eddie Current's review
This and Higher Learning are the only Eva fics with a Peggy Sue element I can stand. In Higher Learning, it's the angle of approach — who goes back: Not a member of the main cast, but a descendant. In Once More..., it's recognition — this is still Shinji, this is still Asuka. Shinji's "backbone" is not so much "Took A Level In Badass" as it is Lets Get Dangerous born of the desperate need not to see the hell he's gone through happen again. And Rei— there are very few fics that creditably get her past her canon status. This is one of them.
FanFicRecs Dead But Still Worth it
I normally avoid dead fics, but I read this WAYYYYY back when it first started, lost track of it during its first major hiatus, and just rediscovered it after the Rebuild Tetralogy restored my interest in the franchise.
Even after all these years, this is still probably one of the best Peggy Sue fics for Eva, one so good, I would even recommend it to people who don't normally like this sub-genre (hell, I can only tolerate it in settings where there's a precedent for something like it to happen, which End of Evangelion actually established).
Shinji is his usual improved self, but its different than most that just magically handwave it as happening. Most just make him strong-willed and that's it, but this Shinji swapped out his depression for a hefty helping of Survivor's Guilt, on top of a heel realization that he let his friends die back in Eo E while he just sat around and moped.
As such, he's putting forward a confident, assured face... much in the same way Asuka does, only less bitchy. The author in turn uses this as the basis for their relationship growing closer, as Asuka sees him as a reflection of herself, rather than someone out to usurp her.
The other major change is Rei, but the fic handles her transformation interestingly. Like Shinji, her change is radical at least on the surface, but when the story shifts to her perspective, the core of Rei is still there; much of her more... normal-seeming qualities are because she's observing and imitating those around her, while trying to understand the context of all the little interactions we don't even think about. It's an interesting take on the character.
That said, the series isn't flawless. Typos *abound*, to the point where certain words are just regularly mis-spelled constantly. It gets a little better, but never goes away, not even with a Beta Reader addition. Also, Shinji's voice never sounds quite right, though that's easily blamed on his new attitude. It still took a little getting used to.
Sadly, the real mark against the series is that it just... stopped back in 2011. Then it came back briefly in 2013, only to stop again. Back in 2014, the author claimed he had the next chapter 75% finished... It's currently 2021 and that nearly finished chapter has never appeared, nor has the author made any further notices regarding its status.
The fic is dead.
But its still good, and worth a read. It juggles WAFF, comedy, drama, and even some action with a decent amount of grace. All in all, i'd say its aged pretty well.