Sometimes I get the feeling that Omniscient in the biblical sense means all-seeing, rather than precisely all-knowing.
God doesn't know everything that will happen exactly, but He's big enough and powerful enough to shape the future such that He knows more or less what will happen, and prophecies will be prophecies, but He intentionally avoids 'looking' at individual futures whenever possible, so to speak, if He can 'know' everything from predictive analysis or what-have-you. From the standpoint of quantum mechanics, to observe is to set in stone. So if He observes the future, He can set in stone that it will happen, which of course destroys free will as applied to people.
Thus, God intentionally avoids looking at it, though he could, in order to allow free will. He may, in some cases, make vague predictions/use His 'peripheral vision' so to speak, when trying to reassure or inform people of their general futures, but if He were to see exactly what would happen for their entire life beforehand, He would be robbing them of their agency, so He only makes vague predictions and cryptic analyses, which has minimal effect on their ability to be free of His influence in that sense.
I don't know if any of that makes sense, but I think it would be an interesting take on it.
Also, God is Good and Good is God. There is no separation between the two in Judeo-Christianity. To do something because it is required of you if you want to be a good person is still doing something in order to be a good person.
I find myself rather annoyed at people who say that you can't be a good person, really, unless you're doing it for no other reason than to help someone else. I like helping people. But it smacks of a sort-of 'if you aren't as naturally good as us, you're not good at all'. And that's not how good works. If you're being a dick about doing something nice, that's another thing altogether, though.