I have 25 photos which should be all of them, but my character index and album are at 98% and 97%, what's missing?
The album count is, to my knowledge, a glitch with the reporting. As long as you take one of all the expansion photos, you should get the trophy for having them all, even if the album is not full. In fact, you only need 24 for it (the initial encounter with Tsugumi doesn't have a specific photo, since you don't have access to Thoutography at that point).
The character profile one, on the other hand, is a flat out bug. You're supposed to get an initial and "true" profile for one of the expansion characters, but it wasn't getting added in the English version. I put together a fix for that one, I'll go ahead and attach that here (I was trying to also see about fixing the NG+ error that some people are getting and put 'em all together, but I'll go ahead and just attach the quickfix for the character profiles).
To use the fix, just unzip the attachment and overwrite the file that's currently in the game, Map008.json, which is in the game's www/data folder. You'll automatically get the missing profile by entering the Clubhouse Village (or just by loading a save that's already there), though you need to be on a run of the game where you've finished the expansion (i.e., not NG+, with the expansion incomplete). The file also includes a folder labeled "USE ONLY IF NECESSARY" folder, which will fix the bug if you are post-true-ending boss and locked in the basement. Same thing, just copy/overwrite Map063 from that into the www/data folder, but as the title suggests, it's a little more of an improvised fix, so use it only if you're already stuck.
Also, for a bit of fun, looks like SQDT's working on a follow-up. "Succubus Olympia". There are a couple preview images on their Twitter and more info coming on Ci-en tomorrow, it seems.
EDIT: There's a hidden hot spring at the autumn area, but it gets locked out if you progress too far into the DLC. Unrelated to the missing index and photo though.
It's needed for the "hidden" Remote Dating achievement, though.