Dave,
If by "create the Amiga Native interface", you mean make ReAction GUI`s for the various parts, then I could do the bulk of that work.
Or are you after a native interface that works across all the different flavours of Amigas?
Well once Henning and co do the sane port, we will need a native GUI for that, as from what little I can remember of using OO.org and scanning it currently (in the Unix flavours) calls the Xsane interface, obviously once Sane is ported we will then need an Xsane interface (be it a port or a new Reaction based GUI) for people to select their scanning options.
OOo uses its own GUI for almost everything IIRC... that one is on all *nixes based on libX11... to test libsane we could use a commandline interface, the network deamon or another frontend that I have in mind...
So there is at least one fully native bit of GUI work to be done, even if OO.org uses its own system with the widgets as discussed by Thomas.
OOo uses its own, make that working, and everything should work
Regards
Mark