I’m stumped by something that is probably simple. I’m trying to make the inset part of this thruster have a semicircular end. I have annotated it in blue
My current thoughts are to make a circle, move it into position by snapping the top vertex to the top point, move 3d cursor to this point and then scale it by snapping the bottom points. Then i knife tool or boolean it.
there must be a better way i’ve missed? I know i can do it already but I want to learn better
I think you should delete the subdivs and use a bevel modifier instead for the first stage. I think you will run quick into a lot of problems by adding details with subdiv modifiers.
This can be done via the “new” blender crease edge approch or the classical control loops…
The crease edge version is simpler in topology but might also be enhanced with some loops on the longer edges. But if you are used to the classic one then the playing with the crease values might be “too much fiddleing” 
… (controll loops can also be partlu collapsed to get a lower polycount)
