I'm worried about the currently winning plan locking up all our dice for ages, and not putting enough focus on getting more influence dice to replace them, so I've done my own plan.
[X] Plan Winning Friends and Finding the Truth
-[X] - Avelorn. A visit to this kingdom will also lead to a year-long ritual marriage to Queen Alarielle, though hardly anything is required of you. Alariel has already given birth to her eldest daughter from Finubar, who will become her heiress, so you just need to keep up appearances.
-[X] - Suppress the dark elves. Probably the main maritime problem for the Old World was and still is your brethren who followed Malekith. Is it any wonder, therefore, that it is better to try to suppress their threat. But it is worth recognizing that when looking to the east, the struggle against the Nors will be weakened. This decision will obviously be popular with the western outer principalities. - 2 dice
-[X] - Not just a formality. Even though the Queen of Avelorn already has a chosen one, a closer relationship with her would be extremely beneficial to you as a king. For many millennia, dealing with her has been nothing more than a formality, but with her full support, there is no force on Ulthuan that can resist you.
-[X] - Reject your titles. Most of the Kings of Ulthuan, since Caledor the Great, have renounced their previous titles as evidence of their future impartiality and willingness to serve not only for the good of their native land, but of Ulthuan as a whole. However, you could keep these titles for yourself, for example, as a demonstration of your loyalty to the agreements that gave you this throne. Undoubtedly, the aristocrats will like it if you demonstrate dependence on them in this way.
-[X] - Collection of information. So far, there has been little progress in the investigation into his death. Perhaps you should make your own efforts to intensify the search?
-[X] - The involvement of the masters from the White Tower may be useful in determining the exact cause of Finubar's death. Right now, his body is being preserved by the Phoenix guards at the Shrine of Asuryan, but you could try to negotiate with both sides about examining his body.
This plan focuses on winning influence and investigating the previous Phoenix King's death.
Supressing the Dark Elves is an excellent action - it wins support from multiple kingdoms in the west, it increases our security, and with the Norse supressed for now we have a window to do it without much risk on that front. If the DC is the same as the Norse action, by assigning 2 dice we have about a 80%-ish chance of a middle success, and a 40%-ish chance of the best success.
One die to charming the Everqueen and rejecting our titles to hopefully gather influence. Extra dice above one appear to have no effect (though correct me if I'm wrong). This is critical, as it gets us more dice, which leads to more actions.
2 dice on 2 different investigation actions. Seems like we have good odds of one of them turning up a lead, and we need to get that done before the trail goes cold.