I've often considered concocting an alternate title card sequence with each of the films in the OT, having NO episode in front of any of them, and setting them to the "theme" song of the episode, just to see how it would work. e.g. Having the Empire Strikes Back logo recede instead of the Star Wars logo, and setting it to the Imperial March.

With the prequels, there wasn't really a good logo that featured the episode name. They were all about the episode number, with the name as an afterthought. And with names like "The Phantom Menace" who cares anyway.

In many ways, Lucas tied himself down too much by putting episode numbers into the crawls.