I'm probably getting too far ahead of myself, but I'm still trying to work out the logistics of how this museum would work.
Would each member organization get their own gallery space or would there be just a few galleries and members take turns in the space?
Maybe there would be rotating theme exhibits, so that, for example, every member would bring in all their mid-century modern pieces, or all graphic design pieces for x number of months.
Revenue sharing is a good idea but difficult.
Does each member an even share of the receipts each day? If so, than larger organizations that can loan more pieces get shafted.
If it is done by per piece, than smaller organizations may not see the value of joining. Plus, if one museum loans a rare piece that generates a lot of attraction they would be get the same as a museum that loans some dusty relic that takes up space. That would lead to trying to measure foot traffic to each piece and figuring out their value in an effort to make it fair.
Again, not exactly something that needs to be solved right now.