What I liked:

The acting was good enough to keep me watching.
The second leads were the sole reason I stuck with this drama till the end. (Even the reason I started watching.)
Dong Hua and Feng Jiu saved the second part of the drama so much, like ugh I lived for the cute interactions. It reach the point that whenever they were on screen, was the only moment I would enjoy the drama.
First and third lives were really good. I started to care about the leads in the third part of the drama, (Mind you I shipped Bai Qian with Mo Yuan before).
Even thought I always stayed away from fantasy cdramas, this one made me think that the action scenes were for the most part quite exciting. It would be sometime until I watch a fantasy cdrama without cringing, but still a great start for me.

What I didn't like:

OMG the second life was terrible. Like Jesus Christ, talk to each other. Things started to go south for me, when Ye Hua decided to keep lying to her after SuSu assured him that no matter what kind of a creature he was, she'll still love him. I could've taken this more easily if there was a genuine reason for the lies. But no, this was all about him wanting to shield her for everything, even of himself.
SuSu was always in the dark, Ye Hua would even abandon her for long periods of time and guess what? Never did he explain shit.
When she landed in the Celestial tribe, he never bothered to explain to her that she needed to be careful with this guy or that one. He was like "Yeah, don't talk to anyone, don't say a word". Like, dude, Who would believe that every person in that effing tribe has ill intentions? Su Jin was so "gentle" with her, of course SuSu wouldn't think otherwise.
When he took her eyes I was done with him, I had to restrain myself to not drop this. I felt glad, when she "killed" herself.
I get that SuSu lost her memory... but Did you all needed to make her that stupid? She went from mischievous kid to Mary Sue so fast, that I couldn't swallow it.
SuSu never went to talk to Ye Hua about the thing that she was mad about, or to clarify the misunderstandings. No couple can last like that. One hiding things and the other keeping quiet about her pain. It's this the couple of the century? Sadly, Bai Qian does this again when she gets her memory back. never letting Ye Hua said his part of the story, and shuttting down everything. Wich made me more mad, because now she knew how evil Su Jin was, all the plotting she did against her. So Why would she still prefer to care only about what she heard of Su Jin' side?

What could have been better:

The CGI, for starters. LOTS of CGI, I wished they would have used more natural locations instead of this huge amount of green screens.
Sometimes there would be issues with the background. Like that time when the hand of the God of Star suddenly disappeared, when Ye Hua was walking and the castle background suddenly changed. Oh, and how to forget that one time the King of the Sea Tribe (don't remeber clearly), passed through a column.
The would use the same 3 or 4 places to film over and over. They used the cave for the Fox clan, for the Kunlun Mountain, The dungeon of the 4 beast, etc. Same with the palace. All of these things really took me out of the drama.
Apart from Male and female leads, everyone used almost the same clothes in all the drama. All day, every day.