I use mostly unrelated names:

Here were the names of my first quint group:
Quaid
Axis
Exmortis
Eckhart
Quade (yes this is close to the first but it's still a real name)

My next batch:
Chaplin
Viper
Wlf
Tags
Draxl

etc.

It's a lot harder to find names that aren't taken but I can't really do the similar naming convention, not knocking it, just can't do it myself.