I really like the Trophy system as a concept. It encourages you to play different dungeons, and vary your playstyle so as to be able to beat different bosses. However, there are two things about it that are kind of irritating due to the fact that most dungeons have randomly-selected bosses.
1) It's all too easy, by sheer coincidence, to get a long string of nothing but the same trophy over and over again. If level 10 bandits or wraiths keep spawning (as they did for me) no matter what you do, there's not much you can do about it.
2) The "IN DEMAND" trophy, though, is even worse. It's easy enough if it's for one of the bosses that's guaranteed to spawn in a certain dungeon, as then you have direction. Otherwise-- or if you're unprepared for the dungeon they're guaranteed to spawn in-- you can easily perform run after run without getting the one the Taxidermist wants.
I think it'd be nice if either the In-Demand trophy occasionally switched automatically (say, every 3-5 dungeon runs) or you could pay a fee at the Explorers' Guild to "tip you off" to one of the dungeons with a randomly-selected boss, which would then be guaranteed to be the one that drops the in-demand trophy. Just throwing it out as a suggestion.