it will be Etherious Natsu vs. Gray...
but I see SasuSaku version of pairing in FT 
I see this fight being as Hiro protraying the two heroes being evil. Basically here we have Gray who is seemingly evil.
Now we know Natsu is E.N.D. means that he'll become evil as well which could mean we're going to get two fights between Natsu and Gray. Atleast that's what it looks like right now. nonetheless I'm still excited.
Ugh.. Don't do that
Juvia and Gray are still better than SasuSaku for sure. Well Aside from the fact that Gray left her for half a year I guess I can see what you mean by that though.
Although I've seen people say how Natsu and Lisanna as a pairing are like the NaruHina of Fairy Tail. Honestly I can see it, but those two at least have legit conversation none of them are shy to talk with other. Granted I do ship NaLi more than NaLu but that's more so because of their childhood and how that relationship's grown. Although I will admit the only thing those NaLi and NH have in comparison are the lack of development/moments. I mean the last time we even slightly got something was when they were in the prison. Then again I'm not too big on pairings for Fairy Tail cause it's pretty one-sided on my part.