Considering the nature of the speech, that is a highly unusual position for you to take. Suppose for a moment that President Bush convened Congress next January for his state of the union and said in it "I call upon the Congress to pass a bill eliminating half of the federal district court benches." Do you think it would be fair to state that President Bush thus favored eliminating half of the federal district courts? After all, it was just one line, was it not?
I for one think it would be perfectly fair because that one line came in his main address to Congress for the year, the State of the Union, and that is the address where presidents always list the top items of their legislative agendas. That is not every item of the legislative agenda - only the important ones. Well, Jefferson Davis' call for the creation of a supreme court came in his own equivalent of a State of the Union address to the confederate congress in 1862. Just as it would be fair to assign a belief from Bush's state of the union next January to Bush, it is fair to assign a belief from Davis' address to Congress to Davis.
It seems more like using the congress as fall guy.
Congress was the body holding up the bill to create a judiciary system. Thus, they were in a sense to blame and for that reason Davis called upon them to do their duty and create one!
That would depend on his actions over the next three years. If he worked for the elimination of the district courts, mentioned it in subsequent speeches, lobbied for it in the Congress, used the powers of his office as much as possible to bring that about then I would agree that he favored it. But if he let it drop then I would just chalk it up to politics.