Tears to Tiara won't be the best anime series you ever see, but it is definitely worth watching for a variety of reasons. Leaf, who designed the game from which the TV series was developed, has a knack for putting together interesting worlds and populating them with enjoyable characters. Unlike its cousin, Utawarerumono, the storyline doesn't get out of control at the end. However, the characters, while definitely enjoyable, are not quite as robust as those in Utawarerumono. but there are a few reasons that this series is definitely worth watching.
1. The use of mythical elements from a variety of western cultural contexts is incredibly fun. Images, objects and characters from the Arthurian legends, Celtic mytho-historical traditions, Roman and Greek mythology, and a host of others are woven together skilfully. I learned a lot, especially about Briton and Celtic mythology, simply by Googling names of characters and objects in the story. My only problem here is with the way the name Lucifer is used. It simply has too strong a connotation to be used so arbitrarily.
2. This is simply good fantasy. There are classic struggles, great battles, heroes and villains and even honorable enemies. It has an epic feel that is engrossing.
3. While not all the characters are deep and engaging (and some are downright annoying), there are a few that are truly fun to watch grow and change throughout the story. And I like the character Arawn far more than his counterpart in Utawarerumono. But Arthur, Rhiannon, Taliesin, Octavia and a host of others are given endearing character arcs.
Again, if you are expecting the best anime experience EVER...this won't be it. but if you want to watch something that you will enjoy and may learn a lot from, this is a pretty good choice