I always ponder the ideas of others. Feel free to chime in. I have a specific plan in mind from experiences with my other camper but sometimes the forum comments make me reconsider after pondering your comments.
Well, yesterday was the day I got started. Just finished a large deck for my sister. One project at a time please.
I managed to get off some of the interior skin to see what was underneath and how the wiring was done as I'd have to tap into it. Since the ProLine Company only put minimal screws into the interior skin as I requested, the panels came off pretty easily. I'm glad to see they are actually plywood not fiberboard. I guess I'll be able to leave them as they are. The wiring from the tongue to the lights (interior and exterior) and ceiling fan looks straightforward and easily tapped. There is a channel at the top edges of the ceiling where they run with room for more.

- Wiring from the V nose up and over. Easily tapped.
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- Some of the panels off to see what's what underneath
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- small two 15 amp breaker box. one breaker for heater, other for microwave and battery charger.
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8 sheets of 1" R5 insulation. For heat but also to keep heat out.
My plan is to have two circuits. One for 110 Volts for the heater and the other 110 volts to power other appliances and generate 12 volts. The first 110 volt circuit will have an outside plug to tap into the campgrounds 15 amp circuit. I have a circuit breaker box with two 15 amp breakers in it. This breaker will only run the baseboard heater (I'll rarely ever actually plug this into the campground) I've purchased a baseboard heater and thermostat. But the heater is 110 volts instead of 240 volts. It's 500 watts so it should easily do the job.
The other circuit will also have a 15 amp from an outside plug to tap into the campground's power. Who two cords and two separate circuits you ask? Well, I've never seen a campground that has power to not have multiple 15 amp sockets. I've been to some that don't have a 30 amp one though. Yes, I'll have two outside connections on the trailer, but one is just for the heater. It may hardly ever be used. Anyway, moving on. The second 15 amp circuit will be for the meager counter that will have a small microwave and coffeepot. the circuit will also power the battery charger.
In my old camper... Little guy teardrop... I only had 12 volts. The battery did a good job and if plugged in the charger easily kept up with the power I was using. I also had a small inverter to convert to 110 volts for my laptop. It worked well, but if I didn't have power for the charger it sopped up enough energy that it drained the battery in a few hours. This time no 110 volts converted from the battery... no inverter. Mine used to send out a whistle when the battery voltage dropped below a certain threshold. I hated it. This time around all is from the battery or a battery that is charging.
My charger is one of those green boat battery chargers from the sports stores. It will charge two batteries at once and is compact and works really well. I've had it for a long time. So, the battery will run
Lights,12 volt TV, 2 USB port wall sockets for charging ipad, and bluetooth radio.
That's it. That's all we need. Been there, Done that... nothing more needed for us.
All of this stuff is either picked up or has been ordered from Amazon and is on the way:

Two exterior sockets for two 110 volt 15 amp circuits.

100 amp battery, AGM, dry cell, sealed metal case. Can be used in any orientation.

Interesting little panel with 12 volt socket, charge meter, and two powered USB ports for charging.

Plates for Coax out to campground cable or to antenna. RCA ports to plug TV into external amp/speakers.

Naxa 12 volt 22" TV with built in DVD, and smart USB connection (plays movies loaded onto a thumb drive). Supposedly had lousy sound, hence the external speakers.

Battery cutoff switch (I have a 30 amp breaker for the battery too and a fuse box for the peripheral circuits

110 volt 500 watt baseboard heater with thermostat

Coleman triton stove
Conform and be dull.