Could use help designing rocket stove w/ thermal mass of water for travel trailer/tent

Hello! This is my first post in the permies forums. I am trying to bring the principles of a RMH (rocket stove & thermal mass) to a smaller, portable scale fit for vanlife/tiny housing. In my situation, I would either be in a canvas wall tent (maybe 300sqft, non-insulated) or a fiberglass trailer. I am a WWOOFer looking to work-trade on properties for a full year or longer, so expect that I will be pitched/parked for that amount of time.

I have attached a simple sketch of my plan.

Obviously, for portability, a mass of cob would be foolish. Using a thermal mass of water in a receptacle of some sort would allow for drainage when on the move. I figured something between 10-30gal would be enough to radiantly heat my space (I know I will have to calculate though and that it will depend on if my space is insulated). I would be building something kinda similar to the system in this video ->

My addition would be an insulated rocket stove, maybe like the one in this video ->

The plan is to have the rocket stove outside of the trailer/tent for safety and so that in the warmer months I can simply detach the pipes and cook on it outdoors without heating the interior of my living space. I would be enjoying the stove outdoors in the colder months still as well. I know I will be missing out on that heat from the actual stove once it's bedtime, but the extra safety seems worth it. The pipes will be insulated.

The water receptacle would be inside the living space. Not only would it be my radiator/thermal mass, but also my cooktop & water purifier (if food grade) once it reached boiling temp that I can use the next morning.

I was also hoping to also add removable trays of some sort to steam food where the pressure is chimney-ed out.

I'm wondering how I can close the system and have the steam cool and return to the barrel like a standard radiator.

I can also use help calculating the size barrel I would need to heat my space yet be a reasonable size, hopefully more wide than tall so that I can make good use of it as a cooktop.

One last thing on my mind: if I detached the pipes & painted the steam chimney black, would the summer sun pull heat from the barrel effectively enough that pointing a fan partially toward the barrel circulate cool air?

Any other guidance would be appreciated, thanks!

The designs could be tidied up a bit, but they are clever.
Search the Permies you will find a lot on the subject of small units.