Having just made a long trip (145 miles down a mountain), I saw when the A/C compressor kicked off (but fan stayed on) and it was at about 7 or 8% , not 5% SoC, as when I arrived to the DCFC within a mile , the station said the car was at 7%. Also, before this happened, the power needle slowly began its march from "max" into the "normal" range and was about 75% of the way toward the red zone.
If you are driving a lot of those 105 miles at 70 or 75 mph, there is very good chance you will not make the 105 miles, regardless of needing heat or A/C. The reason why I think 1.5x the commute range is a minimum because thinking about slowing down, losing heat or A/C, or just being worried every single day about how your driving consumes too much range would certainly not be fun for me. On the way up the mountain, I got a bit too aggressive (passed a GTI driver who was dawdling) and then realized I needed to really conserve energy to make my destination (it turns out I made it just fine with about 15 miles of range left ~10% SoC). If only the e-Golf had about another 10 kWh! Driving is stressful enough, in my opinion, and you shouldn't have the added stress of consuming the entire battery pack energy energy day.