How to render single frames

I am looking for a tool/platform that will let me 3D-render single frames. Unlike the person posting in http://hub.jmonkeyengine.org/forum/topic/rendering-a-single-frame/, I will never have a need for animation, sound, or user input aside from a stream of models/geometries and appropriate lighting/camera setup. The rendered image is my goal, preferably in PNG or JPEG form.

My question is two-fold, plus a meta-question:

  1. Is there a one-shot entry that would let me set up a scene, render it, and then "reset"? It is likely that each scene rendered will have little, if anything, to do with prior or subsequent scenes.
  2. Can the JME3 environment be tailored so that a build doesn't drag in audio, UI, and other packages/classes that I don't need?

The meta-question is, “Is there a better tool than JME3 for my purposes?”

Unfortunately RenderMan is too heavy, both in processing and licensing. POV-Ray is a little too standalone, and doesn’t have any (obvious) Java API. Java 3D is moribund/obsolete, and JavaFX has too much webby crap on it.