Why would someone create such horrible ill-fitting to prophecy elements as the name "Jesus" and the location "Nazareth", when it was the name "Emmanuel" and the location "Bethlehem" that were the significant ones?

Maybe it's down to all the fantasy stories I've read, where prophesies are almost always fulfilled in an unintuitive way (although the Greek oracles were like this too,) but I've always found the theological explanation for Jesus's name entirely satisfying. Emmanuel means "God With Us," and if Jesus was really God incarnate, it would be an entirely appropriate descriptor; his "true name" as it were. And in any case, I'd have a hard time taking seriously the straightforward fulfillment of a prophesy which could so easily be fulfilled by any pair of parents with particularly high hopes for their kid, or by any preacher who decided to pop up in an unfamiliar location and start going by a different name.

In any case, there are already more than enough messianic prophesies to deal with that Jesus never came close to fulfilling in any sense. The entire doctrine of the Second Coming was born mainly as an effort to reconcile all the large scale, unmistakeable achievements that were prophesied of the Messiah with all the things Jesus never did, and the whole census story has about the same degree of plausibility as "some anonymous black man did it while I was in the bathroom".