[EVERYTHING] What role will Euron play now?

Seems like as we are winding down this season, it's becoming more likely Euron won't come back into the picture until season 8. Does this mean he will have a bigger role than expected? I know we have yet to finish Theons redemption? arc and he could very well play a huge role in defeating Euron, but I feel like Euron will leave a huge mark on Westeros before it's all said and done. The dragon horn and the Valyrian steel suit could also still come into play. Thoughts?