Sumireko is actually a genius character and ZUN definitely knew what he was doing. See, she's not one like the hardworking miko or the ass-kicking magician. She's a zoomer who visits a magical place in her dreams without paying rent. She visits, rent-free, to the place that's shrouded in secrecy. And she does it with such glee, even going as far as to demystify Gensokyo by sharing the magic to her Instagram for outsiders to see. She is the perfect representation of an unwanted tourist, which is a good reminder to all Touhou players of what lies beyond the CAVE we inhabit.

It's a great game for Sumireko fans, and a great canon Touhou entry with its own story development and song arrangements. It has a lot of enjoyability, personally.
That being said, is it a great photo shooting game? Not as much as the previous games. The overall difficulty is lower. Teleporting is designed in a non-intuitive way where you have to hold the movement keys for longer if you want to teleport diagonally, but in a quick-reaction game that doesn't fly (many people think the teleporting is broken for that reason). Some fights are pointlessly longer. The nightmare gimmick was cool but could have been a lot more than simple overlapping.

Still good for an afternoon snack