Themes of betrayal, plotting, and true love are unfortunately poorly executed by a meandering storyline hinging on poor communication skills. The biggest issue for me was when the main two characters did not the truth about each other, and constantly tried to hurt the other to hide the truth. It was cruel and unnecessary.

I believe that the surprisingly high rating is because a large number of watchers are first or second time cdramas, who came from being fans of the casts' other productions. Compared to other cdramas, the plots are average at best, and the main character's dynamic is nearly unwatchable during the middle part of the series.

If you want a "sworn enemies, unfortunately in love, navigating palace conspiracies" cdrama that's actually good, try Rise of Phoenixes.

The soundtrack is pretty good though, and some side characters made it watchable.

[SPOILERS IMPLIED AHEAD]
In some ways, the tragic ending redeemed such a storyline, but also made it hardly worth the watch. Forty-nine episodes which I ultimately started skipping ahead on parts just to see the resolution.