Couple aliases I had in mind:
laying_on_front -> on_front and the like, as there already are for lying_on_*
[lying|laying]_on_stomach -> on_front
Any others I'm missing?

http://www.grammarmudge.cityslide.com/articles/article/992333/8992.htm

> Once you lay (put or place) a book on the desk, it is lying (reclining, resting) there, not laying there.

> When you go to Bermuda for your vacation, you spend your time lying (not laying) on the beach (unless, of course, you are engaged in sexual activity and are, in the vernacular, laying someone on the beach).

> You lie down on the sofa to watch TV and spend the entire evening lying there; you do not lay down on the sofa to watch TV and spend the entire evening laying there.

> If you see something lying on the ground, it is just resting there; if you see something laying on the ground, it must be doing something else, such as laying eggs.

laying_on_front -> on_front
[lying<resting|placed>laying]_on_stomach -> on_front
**on front of what?

That's basically what I was thinking - the difference between laying and lying is one people often get wrong, so it's best to alias them both. You're right that "on_front" isn't the greatest tag though. And "on_stomach" was what I first looked up that got me investigating these aliases in the first place.