wrote

And here's the problem:

You haven't described a problem, Jim. You've simply listed some questions about
how such a plan would be reasonably implemented in the "real world".

Suppose for a moment the IARU scheme is done by region for
HF - after all, that's how the allocations work. So IARU reps
from all the Region 2 countries decide how the Region 2 HF
bandplan works.

Sounds like the basis of a plan to me. Probably ought to flesh it out with some
inter-region liaison mechanism, since RF has a habit of crossing the arbitrary
lines that we humans draw on maps.

Does each member country get one vote?

No. IARU doesn't operate on a "one country, one vote" basis (except to elect
the regional officers).

They accomplish their "work" in the framework of a purpose-appointed set of
working committees, similar to the various working committee's that other
international standards bodies use. These committees tend to be smallish, on
the order of a dozen or less individuals and as such do not directly mirror the
demographic makeup of the parent organization. This serves to isolate the
committee from the "politics" and focused on the "best working solution", not
the "best political solution". The committee product is set of recommendations
to be adopted (or modified or rejected) by the parent organization (in this case
the IARU regional officers). Rejection or modification is rare, as the
oppointing body needs to justify over-riding their own appointed body of
experts.

73, de Hans, K0HB