I'll start out pointing some already known facts and then I'll proceed to try to tie 'em up, creating then a profile and a group of risk for his victims.
-First of all, some of the victims had a feet and/or hand removed, whether it is along with the rest of the limb or not.
-Some of them have been found and others not.
-John doe who was a male, but that was dressed as a female, was just killed with blunt-force trauma, and wasn't violated in any way.
-A majority of them were prostitutes, and some others could possibly be.
-People who have a feet fetish, usually get aroused by hands and vice versa, it might have some preference over one or another, but it usually get aroused by both, but why? Cause Hands and feet have a lot of similarities, like: nails, fingers, a different skin texture on the palm/sole when compared with the other side, same bone structure(take a look at the anatomy bones of the feet/ankle and wrist/hand and you'll see what im talking about), tendons appearing when you move 'em, and some other subtle details.Those similarities which may explain why those two seemingly fetishes walk side by side. And those characteristics are really subtle, but are capable of teasing somebody's mind, this is what fetish is, but all of it are generalized in a feet/hand fetish.
-Feet fetish usually is connected with some submissive fetish, because of the symbolism involved in being at someone's feet.
-Some people enjoy sexual intercourse with other people who are alive(majority of us), and some other enjoy having a sexual intercourse with dead people.
So, I believe that LISK is a Male, probably white, straight, not a pedophile, necrophilic feet/hand fetishist.
Who has a sort of Necrophilic feet/hand fetish, I mean, he probably like the usual stuff of podolatry/quirophilia, like licking, kissing, cumming, touching, but with feet/hand of dead women. I believe that the limbs were found in separate locations from the body cause he would remove them for either a fetish purpose of liking the amputated member or for the convenience on the handling, carrying and hiding of the limb, and the discard it cause it wasn't useful anymore or because he couldnt keep it indefinitedly, but it would take a time between the murder, butchering, usage for sexual purposes and discarding of the limbs and for this reason they were found separetly.
This one is sick, but he could've had removed the heads to put them "staring" at him from "above" while he worshiped their feets or hands. This one is an almost delusional especulation, but it was the only way I could explain why he removed their heads, better explanations are really welcome.
He is probably a Male for 2 main reasons: Most part of serial killers are males, so statistically its the most probable and because feet/hand fetish(especially a lesbian kind of it) are not commonly seem on females.
I'm guessing he is white cause I usually find those fetishes more in white men, the reason for that, I don't know.
He is straight, John doe was killed probably because he fooled LISK, who believed he was really a woman, asians have androgynous traits, and they probably met at night, which helped LISK to not notice, LISK could be under the effects of some drug, and he has no trouble killing at all, when he found out that it was man, he got mad and killed john doe with some weapon like a rock, an iron bar or even his hands, depending on how big he is.And he didn't violate the body, neither mutilated it, cause he is an heterosexual, a necrophilic heterosexual, so he has no interest in males, dead or alive.
He is not a pedophile either, cause he let jane doe's no.3 baby untouched, no interest at all too, she probably was murdered cause he had to erase the traces.
Any person who has a hand/feet fetish has some preference, whether it is the sole, the size, the shape of the nail, etc. He probably is not different, so if we can determine what is the common trait on their hands/feet we will probably be able to determine which of them were killed by him. Cause he probably seeks an specific type of hand/feet. For this we would need the photos of their hands and feet which is almost impossible cause its probably in the restricted police files.
I strongly believe that he didn't kill the ones who were not mutilated, and he didn't kill the males, besides john doe who he thought it was a female.
The "group of risk" in here does not include males of any age, elder people of any sex and female kids. He doesn't seem to make any distinction between races, a proof of it is that were found white females, jane doe no.3 who is black, john doe who LISK thought it was an asian, and cherries who possibly was hispanic.
Basically the "group of risk" is females with ages ranging between 15-40, what we could call females on a sexual active age, they could be of any race, and not necessarily a prostitute.
I really hopes this helps somehow, specially the feet fetish theory.