Have just finished the building work on my roll off shed observatory. Only thing left to do is get the power connected. Images of construction can be found at this link. Comments and questions welcome.
An interesting idea. You might want to consider a short roof to protect the computer and you though from dew.
Also I advice is to remove the top plate on the pier. You don't need to level a pier for PA. It will be a source of flexure if you keep the plate and bolts.
Pretty neat observatory. The roll away shed could be handy. Does it block wind from that direction? Although your scope seems well below the cladding walls anyway.