Hmmm, not sure this gives exactly what you ask for, but the PfPOV plug in might at least help you some with what you're trying to do.
I wrote it mainly because I work rather iteratively:
* model some
* generate .pov
* fiddle with the .pov
* model some more
* generate .pov
* fiddle with the .pov
* model some more
* etc...
I wanted a way to generate the .pov without losing the stuff I'd done manually in the .pov.
So, the main thing with it is - you can do all kind of crazy lighting and stuff in the .pov without being afraid to lose it when you generate it again.
Hmmm, perhaps doesn't solve your problem at all ... oh well anyway
for more info see
http://www.perfnurt.se/pfpov.asp