Dr. Wakeman built the XJ series after the Armagedroid debacle, and then you realize that she did so to build a humanistic protector, one who wouldn't be greeted with abject fear everywhere she went. Which is why Jenny is the final model, and the slightly-less-than-human XJ8 is the younger sister.
In Escape from Cluster Prime Vega describes her mother as a, out of all the words in the world, tyrant. Considering that Vexus took away her kingdom's rights to defend themselves, and framed a foreign robot just because she didn't want to become a resident of her home planet, leaving her home planet open for any hostile takeover...
In "Saved by the Shell" after a disastrous date with Don Prima, partially caused by the Silver Shell, Jenny decides that she doesn't like either of them. Jenny never fawns over Don again in the series, but whenever the Silver Shell returns she goes back to admiring him. It could be rubbed off as a continuity error, but it's shown time again that Jenny feels very lonely since she's the only fully sentient robot in the town. In "Love 'em or Leash 'em" she immediately tries to date Kenny simply because he's a robot. Jenny is likely tolerating the Silver Shell's rudeness because she still longs for a robot partner.
One episode features a villain called Armegeddroid. He was programmed to destroy all weapons, but goes a bit too far with his mission. When he comes back, Jenny is able to trick him via his programming into self-destructing, as he is a weapon. In context she didn't have a lot of choice, but consider that since Wakeman created Armegeddroid, he is technically Jenny's brother. She talked her own brother into committing suicide.
The series' conceit is that many robots are people too, with their own thoughts and feelings. Wakeman's decision to keep XJ's 1-8 shut down in the basement is a little harsher in that light, with the additional fact that they're Jenny's sisters. She does lighten up about it later, at least.
The Exoskin from "The Return of Raggedy Android" is still out there.
Jenny, being a robot, will most likely outlive all her friends (and remain in a teenage mindset the whole time.) Although it's somewhat mitigated by the fact that Nora has a de-aging machine, the idea that her friends specifically would de-age when they got too old has its own harsh implications, unless Nora's prepared to de-age everyone else's loved ones.
In the Christmas special, everyone who wasn't Sheldon believed that Jenny had snapped and started destroying holidays out of her own volition. This includes Brad, her best friend, Tuck, who considers her a Cool Big Sis, and her own mother. That's horrifying on two levels. The first is that this episode kinda establishes Sheldon as a Love Martyr (though downplayed since Jenny does give him a mistletoe kiss in gratitude). The second is that even people who know Jenny personally were easily duped into believing that she had turned into a raging monster, didn't bother to investigate to see if there was any evidence that it wasn't her choice to do what she was doing (and in fact were completely unwilling to believe Sheldon's perfectly valid theories on why this was happening, ex. an evil robot double or mind control) and were prepared to shut her down permanently.
The episode "Ball and Chain" has Tammy of the Space Bikers attempt to marry Brad. The fact that Brad's a teenager and is initially uncomfortable with getting married to Tammy (and deciding against it after realizing what their married life will actually be like) becomes a bit more disturbing than it already is when the later episode "Voyage to the Planet of the Bikers" reveals that Tammy is a schoolteacher. Tammy is practically an ephebophile.