My wife and I are watching LoTR together right now - she's never seen the movies or read the books.

Tolkien's characters and relationships and worlds are amazing but his universe's rules feel too abstract and arbitrary for me. Why does an evil immaterial being give dark powers indirectly through rings? The powers of Gandalf and when he chooses to use them seem arbitrary too.

Star wars has less of this problem imo because its magic is grounded in microscopic beings so they tend to exhibit predictable rules and limits, e.g. Jedis need to be trained, grow exhausted, and they use their powers in small ways whenever they can.