Divine- I think it interesting that while Rama in Ramayana was the protagonist i.e. it was his story, he who suffered, he who was exiled. Rama was THE King.
Krishna in MBH wasn't the protagonist. He was the sutradhar or pupeteer, moving his puppets here n there. Krishna was Kingmaker.
Draupadi was his instrument to Kurukshetra & ensure destruction of majority of the Kshatriyas. If he had married her, Kurukshetra wouldn't have happened.
Political - This is something which baffles me. He moved pieces politically so that the Pandavas were made the emperors of Bharatvarsh & Draupadi the empress.
Why not marry the Yadavas-Panchalas?
Why not have aspirations for a Yadava nation then?
If one can say he wanted to be linked to both major nations i.e. Kurus & Panchalas, why not have aspirations for his own clan? Why be the Kingmaker rather than King?
Human - Again he & Draupadi were already friends & got along well. Like it's mentioned in the text, Draupadi did NOT restrict the other wives of the Pandavas, so that argument can't be applied here.
I don't think she would have made any trouble for the other wives of Krishna.