That's a very long post to have this embedded. 😉
The diminishing returns bit is a bit of an annoyance, since one can just cycle thru characters. However, I don't worry too much about it since most of my chars do need something they would get from it. The last thing I'm trying to do is be too efficient, that's a way to make CoX less of a game and more a chore.
On Prismatic Aether prices. I'm fine with them dropping in price, though I don't have any skin in the game. I'm collecting them on my own, not selling or buying. If they drop to a million, I might buy a few to get the badge on my badger. Otherwise, I'll just collect them organically, though I do need to get some ITF & Aeon's in.