For me its NaLu cause I like the idea of Nashi. Also you cant beat the sheer number of times both cannon and filler that Natsu and Lucy have seen one or the other and even now both naked. LOL the Mavis vs Natsu OVA.
HOWEVER just cause I support Nalu heavily I got no issue with Nali other than it would take a miracle I think. That Lisanna manages to steal Natsu's heart. With all the interconnectiveness of the Dragneel's and the Heartfilia's. (Note semi spoiler.)
I support pairings that would have higher chances of happening in the story. So I support NaLu, Gajevy, Jerza, Gruvia, etc. My favourite is in fact NaLu because they are my favourite characters in the series. Recent chapters has shown alot of building up on Natsu and Lucy's relationship.
I ship Nalu because I normally enjoy shipping pairs who are the main characters of a certain fandom. I like Nalu as despite that this ship is normally teased and make fun of by Mashima, the pair would always have their major/serious ship moments in the plot. A few good examples are when Lucy hugged Natsu in GMG arc and Alvarez arc.
