One comment I will make is that this thing, as it stands, has a lot of polygonization (i.e. things that look like polys that you'd never see on an actual ship; that's why the face beveling you had looked so wrong, for the record). I'm really not one to complain as a lot of my models suffer from the same thing in places, but those arms really struggle, to the point of needing to be reworked. Maybe you can make a break in them around the dockpoint so that the arms are independent and can act more like shock absorbers so that the delicate airlock doesn't get damaged in breaching/boarding ops.
Also, working in some extra sides and round elements, particularly in the dock, might be very useful. The standard FS terran dockpoint is round, and will not map particularly well to that hexagonal port.