This got me out of a drama watching slump.
It wasn't perfect but I'm just gonna list my initial thoughts after finishing it and then come back and edit it later.
Warning it's just a jumble of my thoughts right now:

Did not like the end. Thought it fell short!
I wish we had seen more of the Gods world, and like their powers. We saw a small glimpse but not enough.
I loved the FL and ML
I know people hated on the FL and sometimes I get she was far from perfect (e.g. she was terrible to those orphans her dad looked after when she was younger, and was a bad friend to that nurse guy who worked for her), but she was realistic and she did show character development. I think they portrayed their characters really well. They do grow on you as the drama goes on. But I do get why some people think the ML should have maybe been played by an older actor. He didn't really give off powerful mythical God vibes right? And I think part of that may be because we didn't really get to see much of his power that was spoken about so much. And he looks young. But I loved his acting still! I've seen some really bad male actors who have the visuals but don't have the acting talent, but not this guy, you could really see the emotions in his eyes! I loved seeing their connection grow. And I loved how much they both grew as the drama went on, and like what he was willing to sacrifice for her at the end, that was beautiful and sad.
I actually enjoyed the plot, I mean it was lacking a bit but I do have to add I love this genre, and I've read loads of books and seen dramas of a similar nature. So for me, I really enjoyed it even though the ending fell short, along with a few other moments.
I hated Mura! She was so annoying!
At first I hated Biryeom too but he really grew on me, especially as time went on, and we realised his anger was justified in a sense because his close friend died and he had only gone to do the ML a favour probably also related to his love of Mura and her love of Habaek, but then it also wasn't because the guy who killed him was a child at the time, and had been locked up and thought he was protecting his only "friend". And I loved how much he loved Mura, but I hate how he didn't call her out on her serious character flaws. I loved her loyalty to Habaek and was rooting for her a bit, but then she just became petty and selfish, and she was so happy to see FL and ML relationship have problems, she became kind of toxic. I do get how she didn't want him to get hurt again and was jealous because she loved him, but he never led her on, and FL proved how she wasn't like Nakbin and she was still horrible to her. Not to mention Biryeom loved her and treated her way better than Habaek did, and was there for her so long and I don't get how she just didn't see it.