Most metals have a much higher rate of blood dosing when smoked vs eaten. (does depend on the form, and the metal, I know aluminum and sodium are things that are worse when smoked).
Just use lots of rockwool. Get rockwool plugs, rockwool cubes, soak some rockwool in water and tear it down to the size you want. And I agree with the smaller net pots- besides the tipping aspect, I can't see any real advantage to larger ones. Also if you dont have any sort of top feed/drippers, you basically don't need a medium. If there were neoprene collars that could somehow support the damn adult plant, those would work too (this would be dumb tho). Unfortunately have to hold the damn thing up somehow.
I was thinking about ways to grow with just collars, but I really don't know how you could support it from small size to larger. Maybe if you used like 4 collars on a somewhat mature plant
and this. you could probably use whatever the hell you want. I bet you could use styrofoam packing peanuts- anything that won't get eaten away by bacteria. I actually have no idea why mineral/rock based media is preferred at all. Most of them have almost 0 cation-exchange capacity, are oddly ph sensitive (meaning they fucking dissolve somewhat), usually contain some trace bad metals (lots of aluminum) and some other weird contaminants. Also read somewhere that humics/fulvics helps dissolve metals out of the rock material... so why the hell are we using rocks again?