Respectfully, of course people have opinions about this case based upon their personal feelings and experiences, imagining how they might act in a similar situation based upon those feelings. That's normal and I don't think that equating it to a Lifetime movie is an accurate representation.
PR is part of the picture. She was present in the home when the murder occurred, so you really can't remove her from the suspect list. Given what is known about PR's personality and history, it can be said that she did not have a violent history. But it can also be said that she was prone to be dramatic, over the top, insecure about her body and weight as she was aging, flashy, obsessive, attention seeking, very image conscious, living vicariously through her daughter, prone to mood swings from manic high to depressive low. She had gone through a very aggressive and tough course of treatment for cancer, which had left her with panic attacks for which she had to be medicated. Cancer treatment can be brutal, especially back in the 90's. It is literally about killing the disease in the body, which leaves people with side effects and differences within the body that can last for years after treatment has ceased.
PR was also over-scheduled, chronically late and under a lot of stress from the holidays, her responsibilities as wife and mother that were expected of her by her absent but controlling husband.
The assumptions that the note writer was male based upon movie references and a teen who was either manic or on amphetamines are just that, assumptions. What evidence are these assumptions based upon?
We can only assume that the party you are referring to was the one hosted by the Ramseys at their home on 12/23. It was a party for their friends with children. The kids were putting together gingerbread houses with the help of their parents. To my knowledge, most if not all of the kids were within the age range of the Ramsey children. BR was 9, almost 10, not yet a teenager. A manic, drugged up teenager off by himself writing an almost 3 page note would surely have been noticed by someone. Where were his parents? So he waits until everyone leaves and hides out in the basement until late on the 25th? Fantasizing about what he is about to do? Not missed by any family?