I don't really know how this is supposed to be the third in a trilogy - I understand it was marketed as the Harper Hall trilogy, but Dragonsong and Dragonsinger are a clearly linked duology that might as well be one book, and then Dragondrums is book with a different protagonist that nudges itself back into the political complexities of Pern.
I did really enjoy it, for all it was structurally all over the place. It started more like a YA coming of age like Menolly's story, but it didn't end that way.
I was pretty neutral on Piemur overall, but I did enjoy his adventures. Some of the bullying scenarios reminded me of Kel's struggles in the Protector of the Small quartet by Tamora Pierce. I'm glad that part didn't get dragged out too long, though... as I was saying in my Dragonsinger review, I'm just not super interested in school stories at this point.
I think I expected Piemur to do more drumming overall, but the second half of the book was more adventure shenanigans. They were certainly amusing and I enjoyed myself. But as the focus and POV went to adults, I definitely found myself caring a lot less about Piemur and his survival story, and a lot more about what the adults were getting up to.
Overall, these three books were easy, enjoyable reads with a lot to recommend them and nothing I can complain too much about. I've really enjoyed spending time with characters who are not dragonriders, it rounds out Pern. Although, I will say, I am interested in getting back to dragons too! But fire lizards are just as wonderful.