Farming aethyr elemental is probably the worst farming experience that anyone could possibly have in this game. Aethyr elemental is a gold skeleton key boss who drops school design stitch gear that looks like the Elegant style of gear. It's a very tedious fight where the bosses use lots of shields and stuns, and they do very high damage. With a well-coordinated team, the fight takes at least 10 minutes each time.
The problem with this fight is the drop rate of the stitch gear. On average, aethyr only seems to drop a piece of gear every 4-5 runs. Considering that there are 30 different pieces that he drops, the odds of you getting what you want are extremely tiny. I have personally fought this boss over 500 times (I'm at around 550 runs as of this post), and I still do not have the piece of gear that I want from this boss (songster's shoes). I started farming this boss about 5 months ago, and I have spent many, many days either farming Darkmoor graveyard to get skeleton keys, or farming aethyr itself.
The amount of time required to get this piece of stitch gear is way too high, especially since it doesn't even provide stats; it simply exists for cosmetic purposes. No single item in the game comes close to being as difficult to obtain as this.
When you compare aethyr elemental to other bosses that drop stitch gear, there is a clear discrepancy. For instance, King Borr has a very similar drop pool for stitch gear, except his drops are the celestial style of gear. However, all 3 levels of his fights are easier and quicker than aethyr elemental. In addition, the wooden key king borr boss drops the stitch gear at the same rate as the stone and gold key versions. On the other hand, Spirit of Ignornace, a wooden key boss that also drops the elegant style school design gear, has a much, much lower drop rate for stitch gear compared to aethyr elemental (personally, I did 110 runs without getting a single piece of gear).
These stitch gear drop rates need to be improved for Aethyr Elemental. In addition, Spirit of Ignorance's rates should match those of aethyr elemental, similar to King Borr's different difficulty levels. Currently, getting this gear is way too hard and not at all fun. I am sick of fighting aethyr elemental for over 4 hours at a time for months to get nothing that I want.