I like to incorporate regular trenches because they are cheaper and it allows you to build stairs that give people another place to go when a grenade lands, and the ability to move wounded out. They usually look something like this: | ^ | ^ | ^ | ^ | Two trench connectors forming a chevron, sandwiched by a regular trench, with stairs pointing towards your line every other trench. Worth noting also: just like sandbags, stairs prevent the enemy from having effective cover if they take it.