I agree with DD and Rastafla -- the sell price of nymphs should reflect their rarity. If everyone (or almost everyone) who sells a nymph ends up regretting it, that indicates that all those players (and all the players who got nymphs and
didn't sell them) think their nymphs are/were worth more than 909
, and so the sell price should be increased.
In fact, I think the bazaar should automatically adjust the price of every card (
http://elementscommunity.org/forum/index.php/topic,25239.msg356998.html#new) based on the number of copies that are acquired and
not sold -- which would also give players a reason to hang onto Relics. I've said before that if there is no reason not to sell Relics, then the slots should just give electrum instead of a card (which they clearly can do, since they give electrum for matching the first two reels).