[The pictures come up just fine in my browser.]

Nice setup. Random thoughts:

I assume you also have a bunch of portable LED lights that aren't in the photo?

The solar panels will still generate power in cloudy conditions, though at a reduced rate. I often do charging tasks during the day -- the battery just acts as a voltage regulator for the panels and hardly discharges at all.

The solar panels can of course keep the vehicle battery topped off too. Nice to have a backup that doesn't use gas.

The danger with using DC directly from a powerpack or vehicle battery is that there's no protection against discharging the battery too deeply. A car-type inverter, though, will shut down somewhere around 11 volts to protect against battery damage. That's pushing it though; I would never run a standard battery that low. Also, good inverters will stay shut down and alarm; but cheaper ones will cycle off and back on because the voltage rises once the load is removed. A cheap inverter once destroyed a battery in one of my powerpacks by doing that.

In a cold climate, the one big drawback to power packs that use sealed lead-acid "gel cells" is that they must not be charged while frozen. This will ruin the battery. My fleet of powerpacks (most of them scrounged yet functional) comes into the basement in winter.

BTW, where did you get that voltmeter? Neat looking item.