As far as I can tell backup.img and kernel.img are not needed. recover-script probably isn't either. It may also be possible to shrink system.img to the size of its content (50% of it's current size).
There are tangible benefits from smaller files - download speeds increase, cp times reduce and the flash times will be smaller - both due to checking CRC/MD5 signatures and due to flashing smaller images.
Flashing from SD card the recovery program definitely expands system.img out to fill the partition (and this could be done in upgrade-script if it didn't. We need to check we don't break RK Batch Tool, and may need to add to init.rc to expand the system.img (if this is needed)
As far as I can tell backup.img and kernel.img are not needed. recover-script probably isn't either. It may also be possible to shrink system.img to the size of its content (50% of it's current size).
There are tangible benefits from smaller files - download speeds increase, cp times reduce and the flash times will be smaller - both due to checking CRC/MD5 signatures and due to flashing smaller images.
Flashing from SD card the recovery program definitely expands system.img out to fill the partition (and this could be done in upgrade-script if it didn't. We need to check we don't break RK Batch Tool, and may need to add to init.rc to expand the system.img (if this is needed)