there are many chars which i really like in HxH, but i think it's down to kurapica and killuah, and since there was a deprival of kurapica lately, i'd go for killuah.
Killuah is very loyal and altruistic in his behaviour, even though he's a killer and likes to shock and tease ppl with it.
His struggle against his family for his lil sister and for gon is nice to see.
As for kurapica, i like that we have an angel of revenge which doesn't go all out, like in most cases, but analytically goes step fo step towards the distruction of his enemies while still caring about his friends..
On a sidenote, Illumi stepped up by many ranks in the latest chater.
I think he's even more twisted than hisoka in his own way