What are the different ways to unwrap besides marking seams on everything and unwrapping?
Select your object, enter edit mode and hit the U key to access the options.
This brings up a list of UV mapping methods - I assume the complete list (as identified by @sybren though Project from View appears to have two flavours). Complete list excluding the whole seam marking thing that is.
Unwrap and Project From View seem to be the standard 'go-to' in response to a lot of UV questions - though this may not be fact as I've not conducted a scientific assessment of answers.
According to the manual:
Basic: Cube, Sphere, Cylinder, Project from View
Advanced: Unwrap, Smart UV Project, Lightmap Pack, Follow Active Quads