Eh, I think the god-killing thing is really moot. Xena only really seemed to be able to exhibit any extra abilities (blocking/deflecting blasts, etc.) against the gods themselves..
I disagree. On some shows she had trouble with half a dozen warriors but on others she could kill dozens and hardly break a sweat. Her skills were entirely governed by the rule of cool.
Those abilities were also only temporary. Once Xena moved to kill the Archangel Michael, she was stripped of her powers on the spot. Believe it or not, though, Michael actually had it coming, IIRC.
And, logically that should have been the end of it. But in a later episode she defeated Odin, and effortlessly at that.
I think Xena and Hercules got together and beat the crap out of logical consistency early in their careers.