Well, my opinion only, of course, but where are John of Gaunt and Katherine Swynford/de Roët? I don’t believe his first wife, Blanche, was his greatest love. That honour went to Katherine, for love of whom he went to extraordinary lengths, enduring scandal and opprobrium, but eventually making her his third duchess. And managing to legitimize his Beaufort children by her.
As for Edward II and Piers Gaveston. No, they don’t warrant inclusion, I’m afraid. Not because it was gay, but because it became dangerously spiteful, petty, posturing and not a little ridiculous. It ultimately destroyed all concerned. Then Edward II showed even less judgement by moving on to the dreadful Despensers. There was nothing great or romantic about his conduct in allowing his favourites such enormous power. I find his reign fascinating, but always want to shake him until his royal teeth rattle.
Henry VIII and Anne Boleyn? Hmm. That gross man always thought with his codpiece, not his heart. The same goes for his maternal grandfather, Edward IV, the contents of whose codpiece appear to be overactive in the extreme.
Katherine of Valois and Owen Tudor? I have grave misgivings about this one. I believe she was more interested in Edmund Beaufort, 4th Earl of Somerset, and that when she became pregnant and he wouldn’t/couldn’t marry her, lowly Owen Tudor was hastily drummed up to “do the honours” of claiming to be the unborn child’s father. Maybe Owen already had a good and understanding relationship with Katherine? This might have made him acceptable to her in her hour of need. I may be wildly wrong about this, of course, but (once again) it’s my opinion.
Edward III and Philippa of Hainault? Yes. The Black Prince and Joan of Kent? Yes. Richard, Duke of York, and Cecily Neville? Yes. Mary Tudor and Charles Brandon? Yes. Edward I and Eleanor of Castile? Yes.
Who else is missing, apart from Katherine Swynford? Well, Richard II and Anne of Bohemia. Theirs was another political royal match, but they fell deeply in love. He was utterly distraught when she died suddenly.
Richard III and Anne Neville? George of Clarence and Isabel Neville? I think both couples are strong contenders. Whatever else may be said, about the brothers only wanting the Warwick inheritance, and so on, it seems to be an irrefutable fact that the Neville sisters won their York husbands’ hearts. Maybe it can be argued that their father’s inheritance was a great big carrot to both men, but the fondness/love that eventually came into being was real enough. Both men were heartbroken by their wives’ deaths, and George could not cope with Isabel’s loss. Richard, perhaps stronger emotionally, was equally as broken, but did not fall apart as George had done. Am I misjudging these marriages as well? No. I stick to my opinion!
No doubt, you will stick to yours too!