I watched this show for the first time last summer. Since then, I have watched it straight through 2 additional times. I fell that much in love with it.
Now, I'm not saying that a reboot wouldn't be good and/or better than the original, but I honestly don't know how I would feel about it happening, especially with a darker BSG-type tone. One of the things that I loved about B5 was that there was still a light-hearted side to every character, even when times were tough. The same could not be said of BSG.
I feel like some of B5's charm would be lost if done in a different style.