This piece went through a few different iterations before settling on this theme.
The concept is that Powergirl is captured and taken to an unknown world of carbon based life forms . They take on humanoid forms to better communicate with her. The older the lifeforms are, the more dense the material is that they are made of. Hence the once closest to us in this picture is the oldest (possibly made of a material similar to diamond). They regard her as a curosity until they realize that she is kryptonian and refuse to let her leave seeing that she is one of the last of an extinct race. Not agreeing with this plan PG battles to escape.
I chose her old JLE costume because I still feel that it is the most practical. Capes and cleave holes don't lend themselves to brawling.
Bart Sears (who sold me on PG back in the JLE days) often drew this costume as if it was some how metallic. That is what I tried to recreate here.
First... great to see you back! While I personally prefer her classic outfit, there's no denying the quality of your work or greatness of the image. Excellent!