Compiling the latest version of hplip and using cups-1.4, I've managed to print without foomatic-rip/foomatic-rip-hplip and without a ppd installed.
It seems hpcups.drv and/or ../filter/hpcups somehow makes up a driver/ppd dynamically.
So - no perl5 dep and no ppd - happy days
..but still plenty of testing to do.