Looking really good!
Between the museum and rehearsals so I don't have time to check your plans, but
normally... the cabin in such an arrangement is a few steps below the deck in front of it. There would be a doorway closing off the entire companionway (i.e. the cupola here), which entirely hides the ladderway down. So unless contraindicated by your source material, you'll want to move the door much farther forward so it's all approximately flush with the bulkhead.
Otherwise, as currently modelled the companionway is apt to ship water in stormy conditions, leading to a soggy and unhappy captain.

Make sense?