The bold part (usually 3 seperate devices) is covered with a single device called a 'Channel Strip'. I use a 'Presonus Studio Channel'.
The Noise Gate is to shut off the mic at times when I'm not talking (showing things on-screen) i.e so my fans and other background noise can't be heard.
A Cloudlifter or a Soyuz Launcher will help boost the SM7B. They are known to tie hand in hand. They give the mic a boost so that the input (gain) level is good enough, without having to crank up volume in your recording software after you've recorded.
By the way; the problem with hiss through a USB device can be remedied by a USB Ground Loop Isolator.