Right.. all the 3 main men had their character development since that’s the only thing they can do in the story because they’re already rich and privileged.
Meanwhile, the FL is still out here fighting with her trauma; not to mention is still struggling to survive what with poverty and the constant threat of being assassinated still dangling right in front of her.
I don't think she can magically be brave and confident with all of these worries still weighing on her.

It was not that satisfying bc in the end paula hasnt grown at all, she still thinks shes ugly, she still lacks confidence to speak up and she still relies on others to back her up (like whenever someone thing bad happens it always make her more upset of someone comes to defend her) im not saying that it cant happen, but you would kind of expect a well written character to have grown throughout the story, esp the main character. Instead the only well written characters we have are the 3 main men, who have all grown throughout the story. All the women seems 2 dimensional to me, which is sad because this is such a good manhwa