Oh boy this getting better and better.Natsu keep that mentality man through the end,he is a pleasure to watch now.
As for Gray people are forgetting that he has devil slayer magic,which means he can kill Devils,just like dragon slayers can kill Dragons,and END is a devil so it's logical for him to go after END,with the reasons behind it out of the way.So comparing Gray to Sasuke it's irrelevant,I don't want to go why is that,an average mind can comprehend that.
Gajeel looks nice with the council clothes,it's going to be a mayhem out there.I can see a three way battle between Gray,Natsu and Gajeel.
My bet to is that Jerome is a spy buuut I don't want to jump on quick conclusions.