Greetings & Welcome!
Hard sided tents on wheels are hard to beat…
I don’t generally cover my windows, because I like the view in all directions and my van holds the heat in just fine without any added insulation. I do have a good heater though, and have spent winters down to -60°f.
While portable power stations are a thing, they’re too expensive for my tastes for what you actually get. My primary house battery system consists of a used 100ah deep cycle battery, a solenoid, and the cables, all installed for only $80. I made it nicer for an extra $20, by putting the battery in a boat style battery box, and attaching 4x accesory ports to each side of the box, each fused, to give me a total of 8 accessory ports. I didn’t add an inverter because I didn’t want one.
Instead of an inverter, I opted for a $99 el cheapo no name gas inverter generator, and a $29 automatic battery charger. In my normal daily life, everything I use is either 12v or USB powered. The generator and battery are mainly my backup plan, but I do find uses for them occasionally helping other people, or if we need to run power tools in a remote location, or even power an entire group campsite. That setup is ideal for me because it is capable of charging my house battery, my starting battery, and other people’s batteries as well.
For an awning floor, you can get really nice RV patio mats/rugs, or you can go cheap like I do and just use an indoor/outdoor artificial grass rug/carpet available at any any big box store. I actually prefer the EZ-UP free standing type of canopy with the windowed side walls. Mine give you the option of privacy, closed but see through windows, or open screened windows. The best of all worlds. I put down a tarp floor that is slightly larger, and bring it up about 3-4 inches all around the outside of the legs, then put my grass mat inside. The added tarp will keep running water out in case it rains. I really enjoy the option of having walls to keep the wind, rain, and/or bugs out.
"It's always easier to conserve power than it is to create it." ~ Off Grid