Well, let’s look at some of the theological problems.
Since Gap Theory is mentioned I’ll just note that it has problems of its own and many things are described as being created after the Gap. So shoving the problems into the presumed Gap is not a very strong position.
The idea that God has serious opposition in the fallen Angels is a denial of God’s omnipotence.
Genesis 1:29-30 applies only to humans and there is no similar statement regarding animals - not even one giving them permission to eat plants. This is very weak.
Further, Genesis 4 tells us that Abel kept sheep and sacrificed them - and God greatly approved of the sacrifice. Even if we assume that Abel wasn’t eating meat - which seems unlikely - God still approved the killing.
Genesis 9:1-4 is God’s decree. Even if it was not God’s original intent, it is God’s intent at that time.
By Boyd’s own admission the cursed state of the Earth long precedes human existence. To say nature changed in Genesis 3 denies that.
If God used Satan as His agent to achieve His ends, God is still responsible. Boyd must deny that God actually cursed the Earth and say that God was simply stating the consequences. However, God explicitly takes responsibility for the enmity between humans and snakes (3:15) and for the pains of childbirth (3:16). The other elements are more open to interpretation, but given those two the reading that God is both the author and the agent of the curse seems stronger.
This states that once God grants authority, God is incapable of revoking that grant, even in cases of abuse. This seems bizarre. Aside from the implicit assumption that God didn’t know that the abuses would occur or that his chosen agents were unfit for the role, why would God have such a limit ? Humans make provision to remove the unfit from office - why should God lack that small wisdom ?
An omnipotent God doesn’t even need agents. To permit those agents to abuse the power granted them indefinitely is bizarre indeed - and does place much of the responsibility on God.