What I forgot to mention: I think it would be a good idea if there where non golden unlockable legendarys. This way people could try strategies with them and play normal maps but you would still need to do quests to get the golden versions.
Hmm I see your point, but I think then completing quests would become a bit less attractive. I really wanted to capture the spirit of a CDT game with the introduction of expert cards that aren't part of the base card deck. At least those are some epic rewards to look forward to.. Problem right now is certainly that there are so less legendaries around atm. But this will change in future versions, so that the chance to craft a legendary could be higher than now. For instance, in Diablo 2 you were able to find legendaries quite regularily, but some of them, like Windforce were so rare I haven't farmed one in all those years I played it ^^ I think it's a really nice thing to have such rare rewards, to look forward to unlock eventually :-)