Having done "Recollections" (the quest involving getting the "Bag of Seeds" item from elemental monsters in Crawler's Nest, then subsequently getting the "Whine Cellar Key" from demons in Castle Zvahl Baileys) it occurred to me at the time that the portion of the quest involving the elemental enemy target would have been better designed as a popped-target from a dedicated "???" location.
As it currently stands, players have to wait until a weather pattern occurs in the area (Crawler's Nest/Rolanberry Fields.) In practice, because each game day is about 57 mins or so and because weather patterns tend to "trend" to be similar game-day-to-game-day, players can spend whole real-life days waiting on the appropriate weather to occur in-game.
This then results in players unable to progress in this particular quest, which then prevents advancement in the subsequent "Root of the Problem" quest--or even the flagging of the related "Borghertz's Sorcerous Hands" quest (although, obviously, coffer keys can still be farmed up in advance.)
If a dedicated quest-monster ("Elemental") could be spawned by touching a quest-??? instead, it would make this part of the quest less luck-related and more similar to other AF quests at this character level range.
I do understand that with the current leveling progress in FFXI that few players spend much time at this level before advancing--and fewer still make the effort to do the Black Mage AF quests currently--but I think that a better design for this portion of the quest would be beneficial to those newer players that wanted to complete it, without it being such an unreasonable time-investment should they attempt it during a "sunny" stretch of game-time.