Sorahana
for me, their interactions are always adorable... QZ tests everyone's patience but he's a good companion when needed. he doesn't baby YJ by going easy on her but he also helps her in simple ways (just like in the test using their chosen weapons from earlier chapter when he handed her the book while others have to search for theirs)... the same goes for the other young men, YJ's "brothers" as I'd like to call them... for once, I enjoy the wholesome atmosphere around them, motivating one another to become better. in a few years in the academy, I hope their bonds become tighter and closer, and I hope no one has to say goodbye (die)among their group.
Sorahana, this is your story write it how you see fit. As for romance, it happens when it does as I am fine for YJ being 20. Plus by that time both characters would have matured and know each other well. There are main more stories to tell within your story, as long as its interesting as keeps us coming back its fine. This is your path of lilies.
I do agree with Sora. Why does it seems to me that Sora sounds like a protective parent to baby Ye Jiao, though I also don't want baby YJ to be involved in those kind of affairs just yet. She still need to enjoy whatever time is left in her childhood, well hopefully she will still do even if she's already an Eon Master