Billy Burke is a bore. It's not the actor, I've seen him do other stuff. His Philip Stroh on The Closer was truly badass, as well as evil, and Burke earned complete conviction in the character. Antihero is a tired old cliche and about the only TV series to successfully spawn one is Breaking Bad.
David Lyons isn't bad either, but neither his Bass nor Monroe personas seem real. The main villain and the antihero being so dreary really hurts the show. Maybe they should retcon Bass and Miles as lovers and Bass turns into Evil Monroe when Miles leaves him? Desperate, but desperate measures are called for.
Incidentally, so far as nanotech handwaving for the black out goes? There isn't even a suggestion of what precisely nanotech is supposed to actually do
to stop electric currents from flowing. Swarm in to make insulation? Discharge all currents? But where to? And wouldn't any of these make visible changes?
Also overlooked in nanotech marvels is the question of where the little buggers get their energy, deposit their wastes and obtain materials for the new ones they make. It would be very much as though there was a massive bacterial overgrowth. Or possibly it would be more like galloping mold? And they are supposed to have been able to break into every sealed battery on the planet! How? Tiny diamond drills? Sulfuric acid that somehow doesn't cause any visible damage? It's not like the nannites would know one already got into this battery, so that a single practically invisible hole is all the evidence left behind. They'll all
bore in, however they do it, and damage the casings.
Lastly of course, the probability is that anyone using an oil lens microscope, which does not operate on electricity, would be able to see
them, even if there wouldn't be enough magnification/resolution to reveal much about the structure.
Also, what wavelengths would the amulets us to send off signals to the nannites? The nannites are so small that that for each to receive a signal the wavelength would have to be at least in the UV range. Hey, look, Ben's necklace makes my jeans glow! That's a pretty high energy signal. But if the nannites clump to make a longer wavelenght signal receiver, again they are easily visible.
In a movie, you can ask these questions on the way home. But in a TV series, when you just ask yourself these questions during a commercial break, it makes a difference. The passage of a week can really make willing suspension of disbelief even tougher. I suppose the first resort of the scientifically illiterate, quantum woo, will eventually come to mouth.
Lastly, mileage may vary, but the insistence that only the most ruthless brutality could restore "order" and survival seems to me to be more an ideological assumption demanded by a reactionary world view, than a legitimate dramatic possibility.