Aye, everytime I watch Yu Yu Hakusho or Rurouni Kenshin I tend to switch up on which one I think is the best. (I haven't seen any episodes after the Shishio arc, so as far as I'm concerned that's where RK ended)
I enjoyed the character interactions although I'm not a fan of Kuwabara. The guy is definately funny ("How can you keep on hitting a girl like that Urameshi? I mean you even hit her on the ta-ta's") but I find him to be on the annoying side. (Not nearly as annoying as other characters in shonen) To keep it simple, I'm not a fan of goofy underdogs.
I've yet to see the sub and I don't really into on doing so. Seriously, who neeRAB it when the dub sounRAB so good, but then again that's personal opinion.
As far as music goes, there were a few that I liked (Struggle of Sadness being my favorite), but can't say I was a fan of most it. Not saying that I hated the rest of the music, but none of them were really all that memorable to me.
Favorite character(s) are the top 3.. Hiei, Kurama and Yusuke. Don't really hate anyone in the series outside of probably Keiko and the boy with the yo-yo's... What?
I'll get back to you on a favorite saga once I get the chance to see the Dark Tournament. Should be arriving in the mail soon.