How do you control an edge loops direction? I need to learn how to control edge loops. 

I want to get this edge loop to go downward to the bottom faces but instead its tailing off to the side. 

I love box modeling but I keep finding myself stuck in these types of situations where im either focusing on the edge flow and sacrificing how the model looks or ill use the knife tool to cut up nice looking shapes but then have to solve the edge loop puzzle I made for myself.

Is there a way I can understand how to solve these issues myself or a tool that can help set edge flow more easily? Maybe like the poly strip tool from RetopoFlow but instead of adding geometry on top of a different mesh its making cuts top of it instead?

https://s3.amazonaws.com/markets-rails/uploads%2F1533048649070-rf-2.0_polystrips.gif

Edit: I was looking for a more general answer on 'How do you control where the edge flows' I don't normally leave engon. This was something I slapped together really fast as an example. Heres something I use more often. 

How would you get this edge loop to turn where you need it to without messing up the shape of the face? This kind of thing happens a lot.
I know it's not an answer you are waiting for, but maybe use subdivision for edges of those bottom faces, and then move points with "vertex slide"? And then connect vertices with edge making?