I would believe that a stranger did it if not for that ransom note. It's impossible for that note to have been real, so it was clearly written by her parents (i.e. mother). Thus it eliminates the possibility of a stranger killing Jon Bennet
Exactly this. The handwriting, the "small foreign faction," the initials that correspond to a military base that John served on, the amount of the bonus, the length of the note, the location of the note, the fact that it was created on a tablet of paper from Patsy's kitchen with a Sharpie pen from Patsy's kitchen, and that there were false starts of the note found elsewhere in the pad.
Come on! No "intruder" who just killed a six-year-old sits around writing a chatty three-page note on the back stairs after stashing the corpse in a difficult-to-locate room in the cellar, on Christmas day.
Speaking of which, her parents slipped up and put Dec 25 on her gravestone instead of December 26. If they were awake packing for their next-day trip in the last couple of hours of Christmas Day, as they claimed, how could she be killed then? If they weren't involved, it would be far more likely that she died on Dec 26.
There is so much, much more. The summoning of the pilot and plane to leave town the morning the body was discovered (until the police put a stop to that, one of their few correct actions), Patsy being in the same clothing and makeup she left the party in the night before, even though she was a woman well known for her fastidious grooming and fashion; the pineapple, the flashlight, the emergency call in which she and John were heard by the dispatcher saying "we aren't talking to you!" in an aside, even though they later claimed Burke was asleep while all of that was taking place. It's just so obvious. When John carried JonBenet into the living room after finding her (and oddly knowing right where to go in that big house, when the police officer suggested he search) Patsy didn't assume JB was alive, she screamed out something like "lazurus, please raise my baby from the dead like you did for Jesus'. How did she know JB was even dead at that point?
The list goes on. But they were wealthy and connected, and the city attorney at the time did not want to believe that people in that social strata could have done this to their child, nor did he want to antagonize the local power structure.
If they were a black family, do you really think the authorities would have entertained any of that "intruder" nonsense or allowed them to summon friends over to contaminate the crime scene?