The "big thing" that sets this "Reincarnated Villainess" apart from all the others is that here the couple shares a lot of the responsibilities: The female lead is the reincarnated Japanese person while the male lead is the perspective character and narrator; the female lead is the one with knowledge of the future and the game while the male lead is usually the one with the power to put that knowledge to use best; the female lead is the one who is the very embodiment of a good person to the core of her being who inspires everyone to be on her side and do their best while the male lead is cold, fake and calculating with most people who are not the female lead. This makes it really easy to avoid the common trope of putting all the focus on just the reincarnated protagonist who is the smartest, kindest, most powerful and cunning and best at cooking and inventing makeup and gadgets and recipes and making every other character seem boring and shallow to the point where 5 volumes in I still ask myself "Why is she even into him? / Why is he even into her?".
Here the main couple is wonderful although the male lead may take a few chapters to warm up to. I have a friend who didn't really start liking him that much all the way until halfway through the second volume but the female lead can easily carry your investment through the story up until that point.
The side characters work really well too, both by being pleasant on their own and when they mirror certain aspects of the main couples relationship. Personally I was a very big fan of the butler, the princes brother and the princes brother's fiancée.
The setting and plot are never anything too deep or special but the focus of this whole manga are the characters so it's not really an issue that setting and plot take a backseat.
The art and designs are consistently beautiful and exude nobility. My only complaint is that we get SO many great outfits in volume 1 but after that there is far less variety when it comes to clothing and jewelry.
We always get enough nice and warm moments that this series feels like a wonderful journey with a few dark and dramatic moments along the way but the dark moments aren't there to scare you off, just to contrast and make the light moments shine brighter.
Don't let the fact that this series has a sequel make you think it doesn't get a proper ending. The ending is excellent and completes all major story threads in a satisfying way.
If you like a good romance or you just want a unique twist on the "Reincarnated Villainess" trope you cannot go wrong with picking up volume 1 of this series.