I'm trying to base my judgement on the fact that this is a prequel to a full series.  Having never read any of the other books, I'd say this was a sufficient introduction.  Given how short the story was, I have no complaints on the character development.  The writing was crisp, and the dialogue believable.  No insta-love here (yay!).  Best friends to lovers is a trope I enjoy.  The plot could've used some fleshing out, but again, this was not supposed to be a full novel.  I just felt there was no real obstacle to overcome, which left me a little meh about the whole thing.  I'd probably read the next book in the series because I do like the direction the story-line was headed in when it cut off.