I appreciate your summary, as it accurately summarizes my impression of the material as well. I want to piggyback off your conclusion to make a small point.
Now, I don't think Snowden had anything to do with Ukraine, but let's at least keep our minds straight.
As the Snowden leaks named several US technologies, techniques, and even specific targets, it seems highly likely that Russia (and other nations) found actionable information in those leaks which, when acted upon, degraded the US's ability to extract information and bolstered their security posture. Awareness of what an opponent knows about you and can do against you is information that can be leveraged to increase your changes of success and impact.
I agree it's unlikely Snowden caused Russia to engage Ukraine or directly helped the terrorists, but I think it's naive to think those respective organizations didn't use the information he provided to strengthen their stances and hone their strategies. They'd be fools not to. To the extent that there was actionable information in those leaks, Snowden's actions helped those organizations.