Cob remodel of conventional home

Have been casually looking at homes around my area. Of course, anything I could hope to afford in the near future--calling them fixer-uppers is an understatement. The last one looked like a bomb went off inside. Almost certainly they'd have to be stripped back to the studs. Hopefully they'd actually have good bones under all of the mess.

I'm curious about y'all's experience or thoughts on redoing the interior walls with cob. If the place already has good bones, I wouldn't necessarily want to scrap it all. But I'd rather any work I do utilize natural materials, clay and straw are readily available for free here, and I'd prefer the improvements in air quality as well as being able to add sculptural elements for functional and aesthetic reasons. I imagine weight might be the biggest factor, depending on the nature of the floor/foundation. Maybe other ways cob won't play nicely with conventional building methods? As much as possible I'd like to reuse what's already there and keep whatever I add cheap/free and natural. Of course, this is just a broad thought experiment based on what I'm seeing available in my area. There isn't any one site or building in question, so I can't provide more specifics about how this hypothetical home was built (though, if you have suggestions for what I would absolutely want in terms of foundation, etc., I'm all ears... that way I can rule out anything that would be unsuitable.) The county is generally amenable to natural building, so I'm not concerned about the legal side of things, just the practical.

I'd look at light straw infill as the material of choice. Not as dense as cob but still offers the benefits of thermal mass balanced with insulation, moisture balancing, and inexpensive materials.