Despite oldtowm to be pretty reach, I think what euron looks for is knowledge. And the Hightowers like this as well. Oh, and sorcery, too. I think we won't see battes because euron and Hightowers will become allies.
So what does euron really desire? (Lol, it was too Lucifer, now!). I think the iron throne is just a mean, a shortcut, a secondary objective for what he really wants: magical power. Dominating the wolrd. Ok, I know this is stuff to cartoon, but I really reckon it. He wanna be a white walker AND have dragons. He wanna have glasscandle, too. The priests who see the future in the flames, the maegi who see everything in a drop with blood, that blue drink i don't know its name in English. He wishes faceless men in order to kill and die for him. After all, fm are priests and what does Euron do with priests?
It seems ridiculous, I know, but I think that way because of what Aeron saw when he drunk the blue drink. He will get the Iron Throne, but the Hightowers will rule for him while he looks for more sources of sorcery. Remember that shadow Aeron saw. Anyone said in another thread that could be the Mad Maid, but I think it is another girl Hightower: a younger and prettier queen from Cersei' s profecy. She will take the Iron Throne, will become Quibun' s ally and together, they will do experiences with Cersei, like it happens during the Holocaust. What Cersei will lose is her identity as a Lannister and she will beg for her valonqar to free her from this torture named life.
Oh, I didn't forget the main matter. I just spoke about Cersei because someone would use the profecy in order to say that Cersei wouldn't fall until this another queen to come. And please, say to me if there be something y'all don't understand. I'm still training my English.