Sorry it's taking me forever to finish the concept sketches. If you need them asap, just let me know. I can try drawing them more quickly; however, the quality may not be as good.
Here's an update on the work-in-progress I have so far:
Xonos Conscept Sketch (standing)
Also, for the slumped pose, is this the kind of "slumped against a wall" pose that you want?