As fans of Tolkien, we've been mostly lucky that "expanded universe" content hasn't generally tried to alter Lord of the Rings (LOTR) canon. Rings of Power had to rewrite Annatar the Lord of Gifts out of the story because the show didn't have rights to The Silmarillion. But mostly the bonus content around Tolkien's work has only tried to fill in gaps around the canon. But referencing canon at all can be a little constraining, and I often feel about LOTR (and Star Wars and Star Trek and many others) that there's space for incidental stories. Maybe it's time for a show or a movie that's just about a group of adventurers delving into a dungeon to explore. They don't have to run into a Balrog or Gollum or a long-lost relative of Gimli. It could just be a good old dungeon delve that happens to take place in Middle Earth.
The plots for the Shadow of Mordor video game resurrects Celebrimbor, as a wraith, who wants revenge on Sauron. The 3 central plotlines in Rings of Power are Galadriel's search for Sauron, Elrond's work with Celebrimbor, and a bunch of halflings who discover a wizard. Everything directly connected to major plot points of Tolkien's story about the One Ring.
On the other hand, War of Rohirrim mostly just tells the tale of some guy called Helm Hammerhand and his family. It does little more than establish landmarks of Middle Earth. Aside from an obligatory mention of Gandalf and Saruman in the last few minutes of the movie, there's no direct connection to the storyline of the One Ring.
And I think that works really well.
I feel like there's a missed opportunity here. I can imagine a story within Middle Earth that's totally unconnected from anything but the setting of LOTR. Why not follow 4 adventurers who meet in a tavern and end up delving into a forgotten dwarven mine to discover lost magic items?
There's a suggestion of this in the very first scene of Rings of Power. In a brief but stunning sequence, Galadriel and her band of elven adventurers enter a tomb, torches lit, ready to uncover whatever secrets (or monster) the tomb conceals. They discover a mark of evil on a sarcophagus, and then their exploration is interrupted by a cave troll. It's right out of your weekly dnd game, and it feels utterly natural.
It feels natural, and appropriate, because it's an echo of the mines of Moria. More than that, it's a gentle reminder that our modern trope of a dungeon delve was literally invented by JRR Tolkien. The gaming space of a traditional Dungeons & Dragons session, and the framework for many modern ones, is the dungeon as portrayed in Fellowship of the Ring.
Maybe it's not for a show like Rings of Power to stray into casual and inconsequential dungeon delves, but I do think there's room for that within the "historical fiction" of LOTR. Or maybe it already happens on a weekly basis, on the tabletops of some gaming group playing The One Ring or The Lord of the Rings 5e.
Still, I don't think I'd mind seeing it on the screen.