The design has only one flaw that I can think of; the rate of condensed vapour falling onto the plant material and the rate of the flow-through through the cotton filter.

If the rate of the former is faster than the latter then the column will overflow. If the latter is faster than the former then the column may have too little to drip and may extract slower? Or the hot vapour from the surrounding vapour chamber will heat up and evaporate the (condensed) and dripped solvent from inside the plant material? Remember that the plant material + solvent will be as hot as the solvent vapour surrounding it.

In any case the soxhlet design solves all these. But in any case it would be interesting to see this simplified design work!

How does SWIY plan to tether the inner herb-holding chamber into the outer one? Just curious.