I don't think that Tolkien or other classical authors who portray this Kingliness in their writings are really expecting to find it in this world.
I think that it is really a "looking-ahead" to when Christ will reign on earth and He will be all those things for us. He will be our King, noble, brave, and true, etc...
Even Lewis said that if there's something that we desire but we can't find it on earth, then it must be in another world and we are made for that world.
Many things in Tolkien's world have that feeling. You know you'll never really find it here, so I can only hope that I'll find it in heaven someday.
The beauty of Galadriel, the sacrifice of Gandalf, the courage of Faramir; all these are reflections of God. I think Tolkien would agree with me on that.