Here is a novel with deeply developed and detailed original fantasy worldbuilding, thrilling dialogues, well-thought plot and interesting characters:
It tells a story of Kôra - 13-years-old boy, who goes through the series of mysterious events and (mis)adventures, which change his visual appearance and personality forever. During them, he discovers that he has unknown power, which was sealed for unknown reasons. He is trying to solve mysteries about his powers and himself. But this story is not only about him... fairy, shapeshifter, ghosts, potion magus... a lot of very charismatic characters, and which of them has their own motivation and... secrets.
This is remake of old version. It was re-launched this year.
I personally liked old version, too, but this one is even better. Characters became even more charismatic and started to play with new colors. Worldbuilding played with new details. Dialogues became more intense. It shows great writing progress, because author is constantly self-improving and polishing her skills. From time to time she asks for feedback both from readers and from more experienced writers, and always take the critique as a stimule for the futher improvements.
If the goal of these picks is to support aspiring authors, this is a great choice, because I track this novel and know with this person for a long time, and she does really put all of her soul into her work. So I think that if you want to chose aspiring novelist, who is deserving support and inspiration the most, it's her.
P.S. I also appreciate her beautiful cover, depicting the main character, disintegrating into flowers and shards.