We did her with PLD, WHM, DRG, MNK, first we were a bit sceptical if we could even pull it off without a BLM and 2 melee, but to our positive surprise killing the feathers was no trouble at all.

When the fethers appeared we quickly threw out some of our weaker AoE attacks for initial damage on all of them, then chased down the feathers 1 by one after they spread. Only thing that made it a pain for the WHM was that whenever Garuda threw her Pain Wheel attack of whatever it's called it would always hit me and the DRG at the same time behind the boss. : / But after our 5th try or so she went down, was big fun.