I think it would be nice if there was a way to see what badges you are missing while you are in a dungeon, as well as which ones you still / no longer can obtain during the current run. NetHack, that ur-example of roguelikes, has a conduct list that tells you which voluntary challenges you have been adhering to so far in the run.
It would be nice if Desktop Dungeons had something similar, so you can check during a dungeon run whether you've bought something from shops, converted something, or used any glyphs. I think the quest log in the menu would be the right place for that, since there's only ever like two, maybe three quests maximum for each dungeon at the same time.
You could have a list of all the 10 (11?) badges there with their descriptions, have them faded out or solid depending on whether you've already earned them in a previous run, and have the text be strikethrough if you violated the conduct that would let you earn that badge on the current run. Or some other scheme - you're the designer. But I definitely think something like this should be in the game. I hate ending up wasting a run on trying to earn a badge I already had, or being unsure whether I already violated my Miser conduct.
(If there is a dedicated place to post suggestions like this, please let me know. I'll re-post this in the appropriate location if that isn't here.)
Since this is my first post, let me also add my thanks for making a great game like this! I thought the alpha version of the game could already stand very well on its own merits, but the game has come a long way since then, and I don't regret spending the money on preordering! Keep up the good work!