I disagree people follow social codes because it is in their best interests or they are socialized to follow those codes. Threat of eternal damnation has little control over the behavior of most people if it did history would be quite different.
How is determinism any different when God as a Omnipotent being already knows what choices you will make and therefore making Christian cosmology just as determinate. I think the quantum nature of physics works to create a non-deterministic universe but those are different debates from what we are discussing.
Quantum theory introduces an element of randomness, which is hardly free will.
Point taken on an omnipotent God, which is why I have a problem with the Lutheran church I grew up in. I'll likely go Roman Catholic (if I can shake this agnosticism) solely because of the free will issue.