The ending leads over to the second trilogy, which IMHO is better and more mature than the first, it plays a few decades later. I wasn't exactly a fan of how the first one ended (though it was rather predictable) but it really sets the scene.

The prequel is good, and tbh if you consider reading the second trilogy, I'd read it as a filler in between, as it's explaining some of the dynamics with neighboring kingdoms that become important.

Oh I tried another series by the same author - the age of the five - and found it extremely dull. I started the first book twice and never got more than halfway through, then gave up for good.