Thank you for taking the time to review Wilderlands and leave such a well thought out review! I think you did a great job highlighting where the book focuses on and what it 'elides' for the Game Master to decide upon. I personally love when a book gives me more options and guidance for combat as a Game Master, as I don't like to try and figure out combat buffs on the spot when I am running the game - this saves me brain power for what I love to do, roleplaying out social encounters and problem solving, leaving combat to be decided by the dice. This is why Sagas and Songs have so little guidance on when to bestow them - other than specifying you learn them by helping others, it is totally up to the GM to based on the size and scope of their campaign how and when to award them.
If you are looking for a gaming experience that is more like the One Ring mechanically but highly streamlined (including a simplified version of the dice mechanic) I recommend Ever On by Logen Nein - https://logen-nein.itch.io/ever-on-2e - I hope you find the Middle Earth game that speaks to you!