I'm afraid I never found any of the characters in Babylon 5 at all engaging, whether they were human or alien. I did give it a chance, watching most of the 1st series before giving up, but it just didn't work for me.
BSG, however, caught me from the start, and the fact that I found my sympathies flipping from one side to another during the first couple of series was very captivating.
It's season 2 in B5 m that things really ramp up.