(1) Feanor. Anything about Feanor as long he is not protrayed as evil!Feanor. Angsty Feanor is fine. Fluffy Feanor, Adult-Situations Feanor, Forge-smut - whatever. Also, his two eldest sons would be cool. (Maedhros and Maglor).
(2) Legolas and Thranduil - happy father/sonness. Or either one by themselves.
(3) Elladan and/or Elrohir - either by themselves or together. No Arwen. She's worse than T.B. (aka Galadriel).
(4) An evil drabble - from an orc's perspective, or the MoS, or Sauron , or the ickle dark lord himself, Morgoth - anyone from the "other" side... Extra points if Morgoth abuses Sauron somehow. Extra EXTRA points if it somehow involves the shaving of Galadriel's head.
(5) And if anyone wants to write me a drabble where Glorfindel kicks the crap out of Arwen for stealing his horse, more power to you.