I definitely see where you’re going with this, but also keep in mind even before the MC was put in Chloe’s body Ms Colline has been abusing her and mistreating her (which historically speaking, in the past it was considered treason to even speak ill of a royal or noble and was punishable by death whether it was bu hanging or decapitation and I believe this is set in that time frame) and even after the MC became Chloe she still tried to give Ms Colline M U L T I P L E chances to redeem herself and let her off the hook each time. But Colline never learned her lesson and pushed her luck one too many times. I also agree that Chloe wasn’t the brightest for trying to have a picnic in a random forest but i think thats because she was told by one of her maids that it was a popular spot because of how pretty it was. I also can see what you’re trying to say about the whole ex-GF situation but Chloe’s friend noticed what was up and got her over to the store as quickly and discretely as she could.
I'd also like to point out that it wasnt Chloe or the Duke who set the punishment aside from the 300 lashes it was the imperial court who judged her based on her own actions, particularly that of attempted murder (most likely) of a noble that got her the death sentence. While it might be a bit sad that she received a death sentence it is not like her and Chloe were ever close friends or even acquaintances, not to mention before and after she became her maid she actively tried to destroy Chloe for a fairly long time so I don't necessarily see why it would make sense for Chloe to mourn her.
Bruh every time someone gets taken to a movie theatre or play they show a series of frames with them just crying, laughing, getting scared, getting mad etc.
Truly baffles me that she can condemn someone like that and smile and laugh like nothing happened. None of Mrs. Colline's (or however you spell it because IT KEEPS CHANGING) plans were particularly well thought out or had a high chance of working from the beginning. Literally everyone but Chloe and her maids knew that the northern forest was dangerous (I also don't understand why they would just... Walk into a forest that they don't know the layout of, without a guide, without an escort, without horses, to have a picnic. That's just asking for trouble no matter what kind of forest). Literally everyone but Chloe knew what the Duke's ex looked like, and she would NEVER be able to leave the house without passing multiple people.
Yes, hanging for such offenses is appropriate for the setting. But Chloe had one frame to think 'rip Mrs. Colline ╮(￣▽￣)╭' before it was back to tea, crumpets, and romance.