I have thought much the same on occasion and B5 is a major offender.

Baxter's Xeelee books do a fairly good job of avoiding this problem: the humans not only are also-rans compared to some of the species out there, but they repeatedly pick fights that they can't possibly win with beings who they'd wish were allies if they knew what was really going on: the humans may be able to punt neutron stars around but the big boys are throwing whole galaxies.