I hate every other IP that convolutes Magic's own IP. The game feels less and less like magic and more a bag of mixed stuff.
As a longtime Warhammer player, i have to say the 40k decks were exceptional. Still, i dislike those as well. Bolters in magic? No thanks. The style of the cards at least blended in with the normal magic art.
The only cross-over cards that i can live with are the D&D sets, though i thought it was really weak to make the second Commander Legends set D&D themed.
I've refused to use cards from any other IP beyond a few D&D dragons.
The Lord of the rings cards look very cheap to me; the style in no way fits in with normal magic cards. As said, the whole Ring mechanic seems like a real pain to use in the game in the way that i hate it when someone brings the innitiative into the game. I somewhat like the Treebeard card, because the art is by Jesper and could have been any random treefolk in magic. Worst thing is that i don't want to be a hypocrite, but i have a treefolk deck and both Fangorn and Quickbeam are pretty much mandatory in that deck...but i don't really want to use them.
I don't want to hold back people who use UB cards in their decks and i want them to have fun and enjoy themselves, but on the other hand i myself do not enjoy games where i have to play against them. The whole situation makes me sad and enjoy the game less and less.