Small correction: PW has not always allowed two opened clients. They were forced to allow it since one household could have more than one computer and all computers would be logged in with legit players (normally only two).
erebus2075 complaint was not about buying something but that there is more than one currency in the game gold, AD, and seals (four of these that I know of). It seems a little complicated for a game.
I would like the difficulty of Dungeons to be determined by party size or by users choice (less difficult = less exp/rewards to be fair). Yes this can be exploited but then so is Foundery.
Since you can farm AD through Professions and you do not need to be logged in most of the time it takes. I think your argument is a little weak. Plus I've gotten most of my bars and AD from my god (you can invoke once per hour). IDK if a different god would have different drop rates or not.