I think Killua changed his personality from the first season to this re-make. He is now more friendly and accommodating. Whether that is bad or good is up to you. The overall feel of the anime up to the Greed Island Arc is good. Oerall, it was a bit confusing on how several elements have come together: magic, aliens, etc. The Chimera Ant Arc was just too slow. I think they focused too much on it, adding more characters that would be scrapped in the end. There were several series of episodes on the arc where the main characters were not shown at all. And then the concluding arc was too rushed. Did Gon and Killua ever meet again? What happened to Hisoka? To Leorio. And then that anticlimactic part of Gon meeting his father. I thought if episodes were sacrificed on the chimera ant arc for the ending it would have been better.
I really liked the ant king though. But that was also a bit anticlimactic. Also, he looked like Freeza from Dragon Ball. He needs some originality. Another thing that I liked about this anime and the only thing that pushed me to the end is Killua's feelings for Gon. So whe I saw the ending, I was really disappointed that his feelings were not given justice.
