You have to remember that there are four drawings for nonresidents for elk, deer, and antelope.  There is a Regular Random and a higher priced Special Random drawing and both of those are for people who do not have any Preference Points (PPs).  There is also the Regular Random PP drawing and the higher priced Special PP drawing.  The higher priced drawings and PP drawings are held first and the cheapest Random drawing is last.  If there any tags left over from those other drawings, they are placed in that final Random pool.  If there are any tags left after that last drawing, they are placed on sale first-come first-served in July and you can apply right on the G&F website for them.  I'm not sure of the latter part of your statement or where you were looking, but if there was a 15 tag quota with that many first choice applicants, it would have obviously been a very poor unit to draw a tag in that particular drawing.  If you don't have any PPs for a particular animal, there is no sense in looking at anything but the random and special Random drawings for those odds because those are the only two you could enter.  If that doesn't answer your question(s), fire away and even name the unit(s) you need information for and I'll try to give you a helping hand because I'm pretty familiar with their system and have hunted out there since 1992.  You are correct in your assumption that the tags are normally easier to draw where the unit is mostly private property because access is controlled by the ranchers and they have a lot of say so in harvest numbers.