I have a few! I really like Henry II/Thomas Becket, both bc of the movie (love Peter o toole 's incredible "angry omega in heat" energy he brings to an otherwise mediocre film). However my peak dynamic for them is less friends/lovers to enemies in that movie, and more the really fraught dads co-parenting to divorce situation with Henry Jr. Stuck in the middle. Becket himself was just as stubborn and annoying as Henry in other ways and I feel that wasn't portrayed as well in the movie. The Devil's Crown (1978) does a much more accurate job of portraying their dynamic, probably due to the freedom of having more episodes.

As for other ships, I do like Philip/Geoffrey a lot too--they def had a similar close affection before Geoffrey's death, and Philip's extensive grieving outburst at his burial is the first of a long line of what I call Odd Philip Behaviors that seem to break out of the norm of Philip's usual more restrained and formal attitudes and approaches to things. I think they're cute XD if a bit tragic--Geoffrey though I see as a bit too much of a sincere wifeguy to be as into it, but I love schemer4schemer yaoi a lot.

Other ships mostly are all other Richard ships because he's my fave and bicycle, and because people just CANNOT stop giving him boyfriends or boybestfriends in various media lmao, I will say one that is underrated (even by me, I haven't done much of it) is Mercadier/Richard--Mercadier was a loyal and brutal mercenary who was extremely loyal and devoted to Richard until his dying day, almost to a fault (murdered the boy who had shot the king, even after Richard pardoned him lol). I think the similarities and contrast in their personalities is very interesting, not much is known about Mercadier but there's a lot of room for imagination I think.

For non-Plantagenet ships, and to fast forward a bit in time, a friend of mine got me interested in the dramas of Frederick II of Sicily, who also has a variety of fun guys to ship with, lots of tragic bad ending stuff like Frederick x Piero Della Vigna (nothing like driving ur boybestfriend to suicide) but also if he was probably bisexual irl so lots of room for making up ships if u wanted to heh.

Of course there's also the rest of the incest stuff which I don't always actively ship but I think there's lots of cool room, especially for Henry II/Henry TYK which I think is PEAK Dadson material, unfortunately I'm not really primarily a Dadson Stan so I just keep pointing it out to feed those who are into it XD, ALSO I like a John/Arthur of Brittany for more Evil Bad Ending stuff (another thing where The Devil's Crown feeds us well...)

I also have a lil Cathar OC guy who I like to put in Situations but it's probably less "loving" in the "MLM" and more for torture porn BL than anything else. I find it hard to work originally in this space because the existing figures are already so interesting hahaa.

Anyways, I tend to have a pretty tight focus with my personal ships but I always like seeing other people's gay visions, both for education and excitement. I like of course looking for the historical queer corners of history since it's fascinating to see irl interpretations and examples of course, but also it's fun just to look at the weird intensity of the vassal and suzerain relationship and the intimacy that comes even in (and maybe because of) the imbalanced relationships of loyalty, money, and servitude.

This was a long answer but hope it was interesting!