Change Partition Layout?

[Guest emergant]

Given that the internal flash is small and that yaffs2 isnt as fast as it might be, I'm considering moving the whole data partition to the sdcard. Not symlinking it but moving the partition. The thing is I'd need to figure out how to edit the system image I think and probably also the recovery image. Compatibility with updates likely becomes a pain too? Not sure if the benefits are worth it. Wondered what others thought? Anyone done this on other devices?