I think I only saw the theatrical version of TTT a few times after the theater, which is why I didn’t voice my thoughts. I only own the Extended version, since I consider the Boromir scene essential. Let’s see, I’d cut the Massacre at the Fords of Isen, The Song of the Entwives (sadly), The Heir of Numenor, and Ent Draft. From part 2, cut One of the Dunedain, The march of the trees and Fangorn Comes to Helm’s Deep, Flotsam and Jetsam, and perhaps even The Final Tally.

As for TROTK, I quite prefer the theatrical version, with a few exceptions. The Decline of Gondor, The Fall of Osgiliath, Faramir’s extended comments on horseback, The Houses of Healing, Aragorn Masters the Palantir, The Captain and the White Lady, and The Land of Shadow could all remain in. None are essential, but they are welcome.