The final word, as it were, to my question just incase anyone is interested. I e-mailed Jefferson Co to ask about access and this was the answer I got this afternoon...
"Mr. King,
Thank you for writing Jefferson County Open Space. The Ralston Buttes area is closed to public access as it is designated as a sensitive area for the rich wildlife values that can be impacted by human disruption. Access is occasionally provided for scientific and educational purposes through a special activity permit.
As you have indicated, there are multiple private properties in Blue Mountain Estates, and I would caution against any trespass.
Sincerely,
Manager of Public Information"
So it looks like I'll be exploring the north side of 72.

Again, thanks for info on cool hikes out in this area and thanks too for the comments on the photos! If by chance anyone out there receives access for 'scientific or educational' purposes, please PM me so I can come play an educating scientist!
- Stand at the crossroads and look; ask for the ancient paths, ask where the good way is, and walk in it, and you will find rest for your souls.