After much hemming and hawing, I finally did what I knew I should. Many failed attempts at designing a "blank" face/head led me to use the artistic tools at my disposal to create my own template. For my purposes, a blank means a basic template from which other such items will be derived. The template for this blank consisted of half a drawn face (rather than the free GIMP, I used Adobe Photoshop CS3, something I purchased years ago; not the most up to date program, but still good). I used several guide lines first of all, and on separate layers used the pen tool to create smooth, simple lines (width 3 brush was optimal for me). First of all, both parts of the template (front and side view) require the same size circle as a base, with the same height for eyes, nose, mouth, and other details. As this was a blank, I did not bother including hair or other distinguishing features; those will be more important for specific characters and added details.
Once a simple template was finished, I saved it on my desktop for easy reference; it works better for me as a one-man crew, but a team of multiple people is often served better by having a project folder where all related materials are stored. For blender, the work began on a standard sized sphere. I added the template as a background image first in the front view, editing the size and position such that the template-circle of the front view (half-face) matched in size and position to the sphere. The next step was matching the size and position for the side-view's circle to the sphere. Note, it's important to make sure you're working on the same side on both the front and side views.
From that step, it was mostly tedious work, though a tip I give is to make sure that the face is sufficiently flat while you're rendering. Not completely flat, mind, but while the skull is generally round in back, the combination of bone structure and viscera leave the face and front side of the head somewhat flat or square. If you try to render it out, you'll understand what I mean.
The last labor before I considered the face done was filling out the cheeks. While my template drawings took into account such details as the nose, eyes, mouth, and even eyebrows (without hair), I neglected to note the position and depth of cheeks. It's not an issue I deal with most days, and so I wound up with the tedium of moving individual vertices, checking and rechecking, until I was finally satisfied with this blank. I feel it's better to have worried about it earlier rather than later, with each subsequent derivation facing the same tedious issue to the same extent. Once complete, I duplicated the half of face I worked with, and shifted it to the side. I used the mirror tool to flip the face to mirror it's original (over the X axis), and then flipped the faces (so that it would render properly). With the face itself mostly complete, it was a few small spheres and minor editing to give the face eyes, leaving a small bit of editing later to add a back to the head (half of a standard sphere). One day in the future, I'll worry about making lips and a mouth that can animate.