I think that all the reason DFQC listed and the way she behaved toward the moon people is much much more meaningful…
You are so right! There are a few points about DFQC that have not been clarified: apart from what you mention here that none of his people knows where he has been for 30,000 years, no one knows that it wasn't DFQC who had killed the Xilan tribes (he was captured well before that, but even DFQC himself is made to believe that he has killed the Xilan tribe in one of his conversations with Shang Que), he isn't the one who wants wars with the Xian tribe but everyone believes he's the evil one.
Indeed, most Chinese dramas' endings have been executed badly as if the writers and directors just want to pack up and go home. Poor endings are not limited only to fantasy dramas; you'd find poor endings in many modern dramas too. Sad endings or non explicit endings are not considered as poor endings for me. Poor endings are, like you said, endings with no proper closure for all the important characters. Justice doesn't seem to have been served; no lessons learned etc.
For me, I love this drama, but I also have similar issues with the ending. I also have exactly the same questions of "what happens to ...?" I'm so upset that Dongfang Qingcang has never been vindicated that he's not the one who had decimated the Xilan (Xiao Lanhua's tribe) since the killings came after Dongfang Qingcang had already been banished. The Immortal Emperor escapes with impunity for all the lies he spreads (no wonder Dongfang Qingcang hates him and calls him immoral piece of shit) and he'll start wars again sooner or later. He will not stop until he kills all the Yue tribe as this is his obsession. Perhaps the story saves this part for future production, ie. the war of the Xian and Yue tribes continues.
I also don't like how Dongfang Qingcang comes back in the last scene. For me, I don't see Xiao Lanhua missing him like the way he misses her when she was dead. I don't see Xiao Lanhua talking to him, yearning for him to come back. I don't see Xiao Lanhua revisiting all the places they have been to, reminiscing the memories they have together. She looks as it she is getting on with her life as usual. And then, all of a sudden, he appears behind her and says, "I'm back!", as if he's just gone out to the corner store to get some milk. I wish the production had made that scene more romantic like, Dongfang Qingcang's crescent jade (gulan) has disappeared, Xiao Lanhua panics, goes out and searches all over for him, and in a silhouette on the bridge where they made their vows, there he is under the giant moon, looking at her lovingly, and she runs to him, they embrace (like they will not let each other go again) and kiss (hungrily, something like that, more dramatic :D).
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https://youtu.be/bZyXvHJrtoU
https://s.weibo.com/weibo?q=%23%E9%BE%9A%E4%BF%8A%E7%8E%8B%E9%B9%A4%E6%A3%A3%E7%8E%8B%E5%AE%89%E5%AE%87%E7%9C%8B%E7%A7%80%E8%B7%AF%E9%80%8F%23
A ton of his latest shots. Enjoy! XD
For me, I love this drama, but I also have similar issues with the ending. I also have exactly the same questions of "what happens to ...?" I'm so upset that Dongfang Qingcang has never been vindicated that he's not the one who had decimated the Xilan (Xiao Lanhua's tribe) since the killings came after Dongfang Qingcang had already been banished. The Immortal Emperor escapes with impunity for all the lies he spreads (no wonder Dongfang Qingcang hates him and calls him immoral piece of shit) and he'll start wars again sooner or later. He will not stop until he kills all the Yue tribe as this is his obsession. Perhaps the story saves this part for future production, ie. the war of the Xian and Yue tribes continues.
I also don't like how Dongfang Qingcang comes back in the last scene. For me, I don't see Xiao Lanhua missing him like the way he misses her when she was dead. I don't see Xiao Lanhua talking to him, yearning for him to come back. I don't see Xiao Lanhua revisiting all the places they have been to, reminiscing the memories they have together. She looks as it she is getting on with her life as usual. And then, all of a sudden, he appears behind her and says, "I'm back!", as if he's just gone out to the corner store to get some milk. I wish the production had made that scene more romantic like, Dongfang Qingcang's crescent jade (gulan) has disappeared, Xiao Lanhua panics, goes out and searches all over for him, and in a silhouette on the bridge where they made their vows, there he is under the giant moon, looking at her lovingly, and she runs to him, they embrace (like they will not let each other go again) and kiss (hungrily, something like that, more dramatic :D).