I believe that you can say that all the things that happen to Victor are his punishment for what he has done but I do not think you can say that they constitute "poetic justice."
To me, it is poetic justice if the "punishment fits the crime." In other words, if you get what you deserve. Victor definitely deserves to have bad things happen to him. He has tried to "play God" by creating a new life. But I do not think that this means that he deserves to have the monster kill everyone that Victor loves. It just does not seem to be something that comes logically from what he has done. Maybe if the monster had managed to take control of Victor and play God with him, that would have been poetic justice...
Frankenstein's aggressive ambition and devotion to the obsession of playing God resulted in his actual creation of a being. The fact that Frankenstein was acting upon impulse and he was no God made his creature as abhorrent as the nature of its creation. However, in an ironic twist, this horrifying monster ended up having more feel of sentiment, intuition, and self-education than Victor himself- to the point that, in the end, Victor declares that he, himself, is "the wretch". For that irony of events, I would say that it is indeed poetic justice. However, I also agree that Victor's family should have not had to suffer the consequences of Victor's deeds.