I wanted to report in on the results of a little experiment I tried that worked out well for me, and may help some others that are having issue running network cables, or getting MOCA working.
I set up an Apple Airport Express in the "Extend A Wireless Network" mode at a location where I wanted a Mini, but couldn't easily get cabling (actually for me, it's a detached garage / workshop on my property).
Once the wireless connection was established back to the main network, I plugged the Mini in to the Airport with a network cable.
I am happy to report that it works PERFECTLY. The Mini has no idea it isn't wired right in to the main router.
While $94 for the Airport isn't CHEAP, it is certainly comparable to other types of network extenders; in my specific situation, there was no way to run cable out there without trenching.
Hopefully, my results will help out some others.