First of all, as I haven't made a post here before, hello everyone! I've been lurking these boards since around 2013.
The point I will make here is not elaborate, and has probably been made before, but perhaps some good discussion can come of it nonetheless. If we posit that JtR was the killer of (or lead to the death of, if we're being pedantic) Emma Smith, and also the killer of Martha Tabram, might it be possible that the thirty-nine stab wounds on Tabram were not the result of an explosive fit of rage or passion, but simply an OTT way of making sure that the victim was in fact dead, with JtR having become aware of Smith's (at least immediate) survival. Again, I apologise that this isn't exactly a brilliant first post; I will endeavour to make my future threads more substantial.
Good points, mirroring to some extent, my own thoughts. I feel that Tabram was likely a Ripper victim. The killer, having struggled to killer, keep her quiet, etc., evolved in future murders to cutting the throat, thus avoiding the struggle and accompanying noise. I'm less convinced with Smith but the possibility exists, provided she wasn't honest about her attacker(s). However, proximity and timing may point to one man having done for Smith, Tabram, Nichols, Chapman, et al.
Even ignoring the reported gang with Smith, the nature of her attack rules her out as being a Ripper victim for me. The (limited) reporting of the injuries states blunt force trauma to the perineum resulting in a ruptured peritoneum and hence large (but not massive) blood loss and resultant death from peritonitis. In addition she had blunt force trauma to the face. This goes against the canonical five where there was minimal bruising in keeping with hand pressure. That she was a victim of a serious sexual assault resulting in her death is without question, but she just doesn't fit with the Ripper being the culprit.