The batch processor idea is a step back IMHO...
I don't see a problem, as long as it's there someone to code it (and that I sense is
the problem
), to implement my idea, which I think is clearly the most flexible... (it's good to expect anything from the future - the result of the batch conversion wouldn't be revertible)
Even better would be if there was one server-wide default configuration for empty tiles, which could be overridden by a map-wide configuration...
