After reading through this thread, I see that my response is slightly askew of the main focus, but hopefully not so dreadfully so that...well, here goes:
I've always been impressed by the Earth ships in B5. Not because they were technologically more advanced than the other races. Not because of the cool fighter launch mechanisms (or was that just on B5?). But, because, IMO, they look like a reasonable jump from today's (1993 - 2002) technology to 2262. It's only 260+ years. In my mind, our space-faring vessels will be big & bulky, require a rotational gravity engine, etc.
Not to say that I don't like the visions represented by other sci-fi shows (ST, FarScape, and the like), but they just look plausible, IMO.
The other races in B5 had such incrediblly cool looking vessels, that, IMO, could not be reached by humans in 260+ years. At least, not without a lot of external ideas.
But, then again, after sitting in on a NanoTechnology conference the other day...260+ years may be MORE than enough time for humans to bridge that gap between plausible science & ultra-cool fiction. What was science fiction 5 years ago is a reality (or close to being a reality) today, and could be perfected in 10 years.
I babble...my apologies, just thought that JMS did a great job at representing the plausible step of human-tech in the time span between "now" and "the future".
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