This sequel could touch up on a bunch of things considering how much it introduced.
We got White Wich & her Guild Liberos (forgot the name), DEs guild, the Dragon Gods, the new continent itself, Aquaris Key search, Elefsaria his motives & being part of the first guild. What exactly happens if all DGs are defeated.
As for the romance aspect, it defiantly seems like Hiro wants to add more romance to this sequel. Natsu getting jealous at guys hitting on lucy, the whole way Lucy acted to Cana's teasing & the other relationships that have been given attention this sequel.
Also did we ever get to find out what Natsu wanted to tell Lucy at the end of the series ?