There isn't, Michael. I could list horrific murders with no prior connection between killer & victim.
Unless he was already in there, i.e. a punter.
Or maybe Mary Kelly was more extensively mutilated because she was killed indoors and because she was the most physically attractive of the victims? If this was a serial killer who enjoyed dehumanizing women (e.g. mutilating & removing their reproductive organs), that would make perfect sense.
Harry, Mary Kelly was half the age of the prior victims, was known to be in a love triangle at the time of her murder, and murdered indoors by candlelight while she was undressed in bed. Hardly the impersonal pick up on the streets and dark alleys. And the first 2 murders in this alleged series have abdominal focus with almost all of the pm knife work. A dedication that is absent in the rest of this so called series.
There is no strong reason to ponder how Polly and Annies killer met them on the respective murder nights, whether he knew them beforehand, and what his objectives were. The evidence suggests that he acted like a client and preyed on women who had been forced onto the streets that night to earn money for a bed that same night. Both of the first 2 victims were also compromised by poverty and state of being on those respective nights,...1 inebriated, 1 ill. The medical expert in the examination of Annie found that almost all the actions taken with a knife were to obtain what he obtained. That same once coveted organ is left under Marys head I believe. The fact that Polly has several of the same attributes, and is less mutilated, is almost certainly due to the venue, which is changed for privacy next time out,...less than 2 weeks after the first.
From those types of killings to a single throat cut a month later, and a kill that appears to have cuts that are amateur and meaningless in nature, then another month plus till someone gets cut to pieces indoors while in her own bed, that's hardly a breadcrumb trail of a single killer.
And you also skipped over the point I was making about multiple murderers at that same place in time, its a fact, not speculation,...like an arbitrary list of victims by a single mad killer,without a single shred of evidence, is ... certainly.