No theological position, including my own, is free of difficulties. Sometimes it comes down to deciding which problems we are willing to live with. However, I don't believe my problems are as severe as you suggest, and your view has some rather unsavory implications that I shall mention. To begin, you claim that according to Isaiah 41:21-24, what sets God apart from false gods is Yahweh's ability to know the future. Please read the text carefully along with 46:9-10 and 48:3-5. The glory of Yahweh is not that he simply knows what is going to happen. Rather, it is that he can declare what will happen and bring it about—that it does, in fact, occur. Isaiah is not touting foreknowledge but contrasting Yahweh's power with the impotence of the other gods.
Next, you are correct that openness modifies traditional Arminian theology regarding divine foreknowledge and timelessness. Nonetheless, we agree with the free-will tradition in Christian theology against those, like you, who deny both that God can be affected by us and that humans have genuine free will. These are the watershed issues in our debate! Thus, we are solidly on the Arminian side of the fence. However, we do have some family squabbles with our fellow free-will theists and only time will tell whether Arminians and openness theists can resolve their differences.
You claim that if God does not tightly control all that we do, and if God does not know with absolute certainty what we shall do in the future, then God just "fumbles along like the rest of us." This is hardly the case. God knows all the past and ...1