I'm happy to entertain it, but

that particular atom exists because it feels like something to be that particular atom

seems to beg the question somewhat - where is "feeling like something" coming from?

>where is "feeling like something" coming from?

Everytime I think about this, I end up with "the fact that something is not in the state it desires to be in seems sufficient and necessary".

Maybe electrochemical imbalance is what's experienced as consciousness, all the way down to the smallest particles (or even beyond) - then, organic consciousness would just be an immense abstraction of the same thing that drives physics itself.

I feel like this is satisfying, but then again, I'm not Joscha Bach :-)

It's axiomatic. The universe exists because feeling exists. Physical matter is subjective experience. More complex matter up to and including the human brain represents more complex states of subjective experience. The processes in the brain feel like something because a process is a thing.

If my consciousness is only the consciousness of a particular atom, or more likely a fundamental particle like an electron, why do I have the illusion that I'm an entire human animal? How would my vision, for example, be sent to every election in my body, for it to be independently conscious?

And why can cancer hide from my consciousness? If we are a single particle, we can't possibly interact with the others in the way we do - why is that one particle special. And if we are a gestalt, why is it that some of the parts are less important than others. Nerves nicely explain why we are more aware of our hands and lips than the action of our appendix - a singular atomic consciousness can't, and neither can an equally weighted gestalt.