I loved Fred - and Illyria even more. Come on, the tilting her head thing she did was awesome!

5x15 and 5x16 would probably be some of my favorite episdoes. I loved the ending of 5x16, which had Fred driving away to L.A. so optimistic, marking the end of Fred in such a surreal way...
Oh, I also liked Skip, that weird demon who helped Cordelia ascend and who guided her in "Birthday"... he was pretty funny.