Well I believe MQM and ANP also got its politicians assassinated. Now I dont like Altaf Hussain he is an idiot who speaks out of his arse most of the time, but can there be a motivated killing to start unrest by killing her and obviously the blame would fall on Altaf Hussain who was threatening openly. Maybe a third party killed her to blame MQM, after all we have more than one terrorist organization working in Pakistan.
So instead of speculation, lets wait for the evidence and if Altaf Hussain is found guilty than I am sure many urdu speaking people will start hating him because she was very well respected in Karachi.
Also my condolence to Pakistansage and her family for your loss. May Allah grant her eternal Paradise. Ameen