Very in-depth post Onenski!
So why do you not consider your position to be hard determinism? (I see you called it "hard incompatibilism.")
A quick comment before i turn in for the night is that it seems to me that Epicurus thought that "reality' is what we perceive (or experience might be better word). And as I think has already been mentioned by several people in several ways, we perceive that we have the ability to make choices.
Even dreams are real from that perspective - anything that affects us is real; anything that does not affect us is unreal to us.
While I appreciate that it makes sense to look for physical explanations to back up that position (that we have the ability to make choices), in the end it seems to me the force of Epicurus' position comes from the opposite approach from that which draws some people to determinism.
Rather than looking for reasons not to praise or blame, it seems to me that if I think that my life is short I want to make the very most of it that I can. From that perspective, my first and really only concern is that which affects me in some way. What other people do can definitely affect me, and it really doesn't make any difference *why* they do what they do - if it pleases me I should react appropriately; if it displeases me I should act appropriately. Of course the meaning of "appropriately" is going to be entirely contextual, but I would not consider it helpful to my own or to other people's lives to consider myself or them to be unable to make choices.