feel free to contact me at sketchup-house-plans.com and I can set you up with some space to work on this... and perhaps help.
standards would be realisim...
a sheet of plywood should cover 4'x8' with out repeating the pattern or should look correct when repeating...
wood trim should be narrow and long, and should have tight graining.
a cross section of wood should be just that, a cross section, and the outside of wood or the long grain should be just that...
yeah I could get into this.