mind linking the tut? I'm a shit at organics but I know a shit ton about the technical aspects.
what is the purpose of your model. If you are just rendering with a raytracer, you don't really need to worry about your polycount like you would if you were putting it into a game engine.>alpha thing in the textures, it seems kinda complicated
alpha maps are really simple once you udnerstand how they work, so don't worry. It basically comes between a value of 0(black) for transparent areas and 1(white) for visible areas. pic related is an example.>i was careful about not using any triangles, does it really change anything
Keeping it to quads is better for edge flow and topology. If you go deeper, everything is seen as triangles at render time, so in the ultimate scheme of things you always end up with triangles anyway.
Use quads when possible in order to optimize your edge flow, but if there's a situation where you want direct control of a certain surface using a triangle is perfectly fine.