Currently going through the Green Ember series by S.D. Smith again. Its target audience is middle-grade, so you don't have to worry about issues with objectionable content, but I also don't feel like the story is shallow or overly simplified in an attempt to connect to a younger audience. There's a surprising bit of depth, and on more than one occasion was significantly though provoking to me personally. It actually has what I would consider to be a very creative and moderately deep lore behind it (of course not as deep as LotR) and toward the end of the series it is integrated into the main story in a very unique way. The tone can change throughout from lighthearted to surprisingly grave, but the grave parts are never meant to feel depressing or nihilistic, and the author doesn't add anything for "shock value" or any foolishness like that. It's a mixture of tones, and honestly the lighthearted and/or comedic parts are some of the only times I have ever laughed aloud when reading a book. There are also a few companion series that are supplemental to the main
books, the best of which in my opinion is called the
Tales of Old Natalia. Those books are narratives that tell stories which elaborate on the lore that is essentially legendary history in the time of the main story. The series may not be as deep as some others, but it really is an enjoyable read that even got me interested in learning about the lore behind it. There are plenty of inspirational moments and satisfying character arcs. This is one of the few book series I can wholeheartedly recommend with basically no caveats.