Others have given you plenty of good advice, so I won't repeat it. However, what you do depends on you and your family's risk tolerance. I've cut my EV teeth with the 2011 Leaf (70 mi range when it was new) and continue to drive it daily so I'm able to drive without much anxiety. I've only had two moderately concerning drives with the S70D, one with bicycles on the back driving 80 mph against the wind and in the rain (oops, I knew I should have slowed down earlier, but still arrived with 10 mi range), and a 150+ mi leg against 30 mph head/cross wind in a snowstorm (again, 80 mph at the beginning, oops). I always have several backups to reduce risk, each of which will add time (so have some good books/games), but slowing down is always the easiest. You can get amazing range at a constant 40 mph, even in the mountains. Don't listen to folks talking about lousy range in stop-n-go city traffic during the winter (which uses huge amounts of battery to warm up after each stop). Continuous driving at moderate speed, even in winter is completely different. If you start out with a full, pre-warmed battery and cabin, drive continuously until you stop (and then immediately charge), you will keep the battery warm and have better range. If it was me, I'd do a short stop in Grants Pass (85 mi) and pick up coffee at the Human Bean, 120 mi to Mnt Shasta for a long charge (60+min & lunch at Best Western or Rays grocery), then 130 mi to Susanville for an early dinner, then 90 mi into Reno.
Sorry, maybe I wasn't very clear. Yes, Susanville has several 240V Level 2 options (hotel & RV park), just check
www.plugshare.com. If you spend a couple of hours charging over dinner, you might get an extra 50-100 mi buffer. For the RV park, take your mobile cord with the 14-50 & 5-15 adapters, plus a good 10 to 12 gauge extension cord. The 5-15 adds maybe 50 mi overnight, 3-4 days for full charge, but helps keep the battery slightly warmer and eliminates vampire loses.
Here's more info:
Susanville traffic on a 4th of July holiday weekend?
Shasta City through Susanville to Reno