I've spent nearly 5000 coins in the coin launcher, done over 60 minutes of heavy-duty sticker factory play (not all at once, I know the sticker count resets), and collected quite a few random other stickers, all since I got my 625th sticker. Nevertheless, none of this has gotten me ONE new sticker! This leads me to question if there are certain objectives that must be completed in order to be able to get the remaining 75 stickers. However, the only challenges I haven't completed are clearing Boss Battles on Very Hard and Intense (grrrrr), collect 500+ trophies, collect all stickers (obviously), and "beat ____ with everyone" challenges! Furthermore, I cleared the SSE at 100%, unlocked all of the SSE videos, collected over 400 trophies, and already completed [EDIT: 115] of the challenges. Does anyone have any insights as to what I can do to unlock these last few dozen stickers?