In any case, it sounds like we are agreed, that the bare essentials are what are at hand here.
And for the original question...
Well... it's an interesting question... and it's vaguely related to the other thread on nama-rupa.
Because if we start with form... we can ask if as a khanda it refers to matter, or simply to form as perceived mentally. Or if this is a valid distinction, or one that is better not worried about.
In any case... it goes without saying that there is no self in any of the world anywhere... this would include the earth, etc... Who could fathom a self in the dirt? That's why the buddha asks us to contemplate our bodies... Essentially they rot together with the ground... And the air in our body is the same as the air outside... So this is form... And it's not ours. And it is bound up with suffering, and it is impermanent in the sense that it's not fixed and can be twisted and torn apart at any moment. And, then we have... what's the other one... feeling. There are no feelings to be found outside the body... if they are we might as well include them in the body... I mean, what is external besides form? It's the only one really. And it's only external because of our mixed up perception. Hm. So that's interesting. And naturally if you cling to form perceived as external, that's suffering as well. Because it can be taken away just as easily.