Baz yes you are correct on the edge loops thing its mostly for animating and creating good deformations especialy in the face during animation! As far as quads and tris go i can only state my personal feelings on this after modeling for a year and talking with people like wiro, stahlberg etc I think that many of us have come to the conclusion that quads are best but strategicly placed tris are often a better solution in some tricky areas As far as rendering goes quads are actauly divided into tris for the render anyway and stars (where more than 4 polysmeet ) are a definete pain but as you said almost imposible to avoid n gon polys or polys with more than 4 sides render out well in some apps for example mirai but wont work at all in others As far as showing the exact tools ill be using lw but the methods and tools for general modeling like this should be similar and ill try to explain it very clearly