I perforce accepted this canonization at the time (going back to the early 1970s - in real time I heard a number of their great late-60s singles but not really the albums until around 1970). But even now it's hard to get past the hype, and to avoid holding it against the album.
On balance, I think the Sergeant Pepper album is great at both ends but weak in the middle. And the concept is a bit too McCartney-weighted, rather than being more properly balanced. I do happen to like John's song "Good Morning, Good Morning" more than many do. To me it evokes ennui and desperation, rather than just being a throwaway.
Perhaps the album would have come out more consistently strong if they had held back Penny Lane and Strawberry Fields for it (although those two songs made a perfect and truly great single - possibly their best unless you prefer Hey Jude/Revolution). But I prefer to the Sergeant Pepper album, at a minimum, Rubber Soul, Revolver, and the White Album (despite or perhaps because of its imperfections). Also Abbey Road if one overlooks a couple of its weakest songs. One could also very reasonably prefer, say, A Hard Day's Night, although that raises commensurability issues. And even the lightly regarded Help! has an astoundingly strong Side 1.
So that brings us to the reissue, which if you go whole hog is 6 disks and more than $100. But I've decided that getting to listen to the remix, plus the outtakes from CD-2, on Spotify is good enough for me. I'll live without the outtakes on CDs 3 and 4 (insofar as I don't already have them), given the price.
One problem with Sergeant Pepper outtakes is that they tend to sound a lot like the finished album tracks, minus all the touches that were added in production. Outtakes from other albums, when they were doing more live playing together and sometimes took detours before finding a given song's final form, tend to be more interesting. The one exception here, Strawberry Fields' with its fascinating evolution, has already been thoroughly covered elsewhere, especially if you don't limit yourself to the official releases from Anthology 2.
Next year will be the 50th anniversary of the White Album, and that could REALLY use an expanded reissue. Despite some coverage on Anthology 3, there is lots more. For example, the complete Esher Demos (Beatles Unplugged in George's house right after they returned from India). This has been bootlegged but ought to be released officially. Revolution Take 20 (the "take your knickers off" take), which shows the join between Revolution 1 and Revolution 9. The full version of "Can you take me back where I came from?," although they picked the best part of it for the album. Paul's loud-soft-loud run-through of Why Don't We Do It In the Road. Whatever they have of John's demo take of Good Night, which I gather is incomplete but gets merged into the released version on Anthology 3. Maybe the long version of Helter Skelter, although my impression is that it's probably a bit dull and draggy (they wisely sped and amped it up for the released version). And there is probably more, such as early takes of songs from Let It Be and Abbey Road that were demoed at this stage. Anyway, all that would be a real contribution, for which I might be willing to shell out > $100 if Spotify only had some of it.