"Wonder if by only asking for a 25% reduction in the Monument size will limit or lower the litigation exposure if approved?"

In my experience, and with many years and thousands of hours donated to preservation causes, I can attest to the fact that most activists in this area are rabidly devoted to their cause/causes, and not inclined to negotiate.  Yes, I am a credentialed master land steward, but unlike many of my fellows doing such work, I believe there must be a balance between different types of land preservation, and the different kinds of land exploitation.

By the way, readers here may find it interesting to know that most land under legally prescribed preservation in this country is privately owned.  In my opinion, that's the way go.  If it's worth preservation, buy it.  The Wilderness Society is the best known example of this in buying and managing property for preservation (while allowing limited pubic access), but there are lots of small groups doing much the same thing, as well as buying preservation easements, or accepting donations of easements on private land (for which the donors get tax write offs).  I've worked with some of those groups too, and helped them on annual inspections required to sustain their rights if challanged.

FWIW