Enough Solar for conservative boondocking?

We started boondocking for the first time last year. We went on three trips where no power was available. Each trip we used an average of 75AH per day. That was furnace at night, LED lights, Water pump, Propane fridge etc. The typical setup. We found that in May when the sun was high in the sky, we were able to recharge our batteries without issue using our 160W suitcase solar. Same thing in August. Our camping trip in October, not so much. The sun was so low in the sky, we had to supplement with a generator to get the batteries back to 100% each day. The time of year, whether it's cloudy or sunny, how much power you use all play a roll. A lot depends on how much you are willing to do without too. We have friends that boondock a lot and they have one Marine battery. Not even a true deep cycle. They use no power except a light when getting ready to go to sleep. They utilize the campground facilities, wash dishes in a pan after filling their water jug, add another blanket if they get chilly during the night etc. It can be done. You just have to know how conservative you're willing to be.