Why don't we just use the regular "Newbie", "full member" "Hero member", etc?
Or, if we want somethign creative, have something like this
"Light Emiting Diode" for one star
"High Pressure Sodium" for two stars
"Metal Halide" for three stars
"Mercury Vapor" for four stars
"Incandescent" for five stars
The more stars you have, the older your streetlight light source is. and maybe have the light bulb icons that appear have the light source that matches the name like a person with two stars would have two HPS light bulbs? We dont have an LED or MH icon though.