This makes a lot of sense. I was since able to follow Ponce-De-Leon's instructions from here to use the very same theme he uses (as opposed to fully reverting) and, for some reason, while the background works perfectly and the title and footer fonts appear to work beautifully too, the text for the actual entries looks like the default, unicode (?) font. The icons work perfectly fine too, interestingly.
I'm perplexed as I followed his (and your) instructions to the T! That is, I placed the theme folder in both the /usr/share/grub/themes and /boot/grub/themes folders (with the former requiring me to run nautilus using sudo to do so). I tried pointing GRUB_THEME in the grub file to each location and updated grub thereafter in each instance, but the result is the same. A near-perfect grub screen, but with the actual boot entries in that ugly default font. 
Out of curiousity, is there any meaningful difference with the grub theme residing in the themes folder that is nested in /usr/ versus the one in /boot/? Why are there two folders for grub, anyway?