The Job passage are the words of a man, Elihu, who isn't even called a "prophet". Same issue I have with using the Psalms as a theological reference: there's no authority given to the speaker. Lots of people say lots of things in the Bible; there's really no reason to trust Elihu's word over Ross', from that perspective. Believe me, there are some actors in the Bible who, although favored by God, are not good models in all their speech and actions (take Jacob, for example).
The Isaiah passage illustrates perfectly my earlier point: the future being discussed is future acts to be committed by the Lord. Read the passage again (esp the bold bits) with that tenor in mind and it becomes perfectly readable: the "smoke will rise forever" because of the actions of the Lord, not some third party.
The current problematic passages for me are more along the lines of, "Babylon will do such and such," or more specifically, "Israel will be taken into captivity." For example:
Genesis 15:13
Then the LORD said to him, "Know for certain that your descendants will be strangers in a country not their own, and they will be enslaved and mistreated four hundred years. (14) But I will punish the nation they serve as slaves, and afterward they will come out with great possessions. (15) You, however, will go to your fathers in peace and be buried at a good old age. (16) In the fourth generation your descendants will come back here, for the sin of the Amorites has not yet reached its full measure."
The "enslaved...four hundred years" bit requires either 1) true omniscient foreknowledge, 2) a decision on God's part to take over human activity (i.e. God is the one willing the slavery), or 3) omniscient "present" knowledge, i.e. that God knew what should probably happen based on present events and the hearts and minds of the Egyptians. It's an epistemological quandary, but from my point-of-view no more "risky" than saying God "just knew". I feel my theory both supports topics already resolved under the omniscient view, AND opens up explanation for some of the "unresolved issues" with omniscience. One of my favorites of which is Jeremiah 3:6,7
"Then the LORD said to me in the days of Josiah the king, "Have you seen what faithless Israel did? She went up on every high hill and under every green tree, and she was a harlot there. (7) I thought, 'After she has done all these things she will return to Me'; but she did not return, and her treacherous sister Judah saw it."
This is God speaking for Himself, and He says "I thought one thing, but something else happened." How can an omniscient God say this with a straight face?
Still pondering...