I don't think I could buy that; Marisa is pretty nonchalantly hardcore that I don't think you could possibly "fake" it.
- Reimu: A priestess who can quite literally obliterate anyone she wants and can be affected by the world as much as she wishes.
Well, not that she would, but the rules of battle pretty much prevents needless bloodshed. She could certainly do other things, but actually killing a youkai (along with killing a human) is forbidden. Yukari however, likely holds that authority (among youkai sages) but Gensokyo is a place where you don't need to use that authority. It's making me wonder how 'common' human-human murders work, though.
- Yukari: She controls Boundaries...all Boundaries. Between Life and Death, Existence and Non-Existence, Here and There, Male and Female, Dreams and Reality...choose your pick.
While that is the case, it's been shown that Yukari doesn't really
actively use strong boundary manipulation. She passively uses it in maintaining established boundaries and commonly does (small) spatial boundary creation, but those even sound easy to pull off. In addition, she gets tired using boundaries in excess, what with actually needing to hibernate, what with her body needing to regenerate, what with her just plain not abusing boundaries all the time. I'm fairly certain that each boundary is variably difficult to manipulate in contrast to another boundary. It isn't just like "oh i'll just make gravity reverse just for the fun of it"; while it sounds fun to imagine I'm sure that doing something like that would be extremely difficult, if not impossible. If one boundary is altered, it can trigger another that needs to be changed, and others, and so on. Something like spatial boundaries have two pretty well-defined sides that are easy to access, so it probably doesn't take much effort. Wiping someone out of existence or turning dreams into reality, should be leagues more difficult. While there are two sides to a boundary, it's definitely not just the flip of a switch.
- Yuugi: A Deva that control supernatural phenomena...in others, pretty much all of Gensokyo.
Yuugi's control over the supernatural could imply that she can control the youkai and ghosts of Gensoyoko.
Ehhh Yuugi's powers are better left to speculation and be forgotten. She's never used her powers for anything, and she doesn't need to. She's an oni. It's like Yuuka not really needing to use her powers in battle because her own inherent strength trumps her ability.
- Suika: Controls density...what's stopping her from growing into the size of Earth? Creating a blackhole? Creating her own star?
considering her utter disregard for the laws of physics describing density, probably nothing, i mean she did blow up the moon (see later point)
- Letty: She controls cold, in other words, she takes away heat...a molecule's vibrations...she controls Entropy. And she's a mother figure to Cirno!
Nnnnope, on both statements. The extent to which she controls the cold isn't described, but please don't make outrageous speculation like "she controls x so she ALSO controls everything related to x to the utmost extent!". Cold doesn't even have anything to do with entropy. PMiSS shows that she doesn't really show Cirno in high regard, either. Makes her look bad when people equate their powers.
Suika shattered the moon. considering the princesses of the moon can curbstomp Yukari and Reimu in a fight... Suika is technically one of the most dangerous beings in Gensoyoko.
To be more precise, she blew up the reflection of the moon. In Gensokyo, you cannot see the real moon; the sky only reflects the real moon and that is what you see. To an incomprehensible extent, Suika ripped open the sky and this shattered the visible moon.
i talk too much about these things