Nice build, you don't screw around
Given that I may very well never actually use my build (i.e. a real half or multi day power outage), I didn't work too hard on mine past what I posted, but about the resistor, I found out that my inverter, would sometimes charge too quickly even with the resistor and trip the DC/DC system, or maybe my DC/DC system trips more easily now, so that's why I put a bigger resistor now.
I found I had issues during software upgrades where the DC/DC turned on and off a bunch of time and would eventually trip.
I've also added a simple inline switch before the resistor so that I can turn the entire thing off and it won't try to energize unless I actually need it.