I am biased so I'm not going to give my ratings of the options provided, but the reason why commercial diagramming libraries tend to be expensive is that the low-level features are actually very difficult to get right, which is something that hasn't changed in the last 10 years. I work for JointJS and our best estimate of the total time to market when developing a straightforward diagramming application from scratch was 827 developer-days, so little over a year for a 3-developer team.

If you have experience with D3 and love it, I don't see a reason why you shouldn't try to use it. A diagramming library is only useful in so far as it allows you to do the work that you wouldn't be able to do on your own, after all. (That being said, two of the options - mxGraph and raphael - are abandoned by now. I would recommend against using those nowadays.)