A small, studless cargo vessel I designed for the sake of using those triangular structural pieces. The back is for engines, the front is for sensors. Its capacity is 4 SNOT Boxes and a droid pilot.
Main view with landing gear deployed.
Half a SNOT Box. Each box consists of two identical halves connected by four technic pins, and has a capacity of more than 300 cubic studs.
Side view, with the "S" emblem of Systemwide shipping company. ("SysWi: it's the new FedEx.") :)
Rear view with engines and ladder.
The door at the back swings up and inwards to save space. There's no airlock, because the droid pilot is insensitive to pressure change. Notice here the seat (which rotates) at the top of a ladder inside.
Side view with panel removed, showing the SNOT construction. The angles come from 1x3x3 1/3 inclines with studs, and all the upside-down pieces are connected by technic pin joiners.
Great design and the triangular shape and cargo container layout make it look like a bit like a modern oceanic freight ship. I would suggest putting a bit more detail on the bridge in the rear and using SNOT to break up the boxy shape of the bridge.