Many thanks to the Op @cliveshep for starting this thread, very useful, sensible and probably timely for many of us, a good call-to-action to dedicate some thought and action to this delicate subject.
Some very useful responses, info and links.
Specifically happy with the link to Amar Retatriations, the idea of pre-paying for the cremation is perfect, takes a lot of burden off of grieving f&f.