My surveyor and a good friend with far more experience both suggested I replace my line with cable,..... To me, the chain stop seemed more simple .( It is but you may not have enough room between the anchor shaft & the windlass to pull that off. (Maybe it's just the camera angle that seems to limit that needed space for a chain stopper.) I like the cable for a chain stopper as well!
I like your wash down hose solution too. My boat has no locker access in which I could stow the hose, (Neither did mine, so I simply had 2 hose bibs mounted on the bow, one for raw water and one for fresh water. I washed all the mud off the chain & anchor with sea water then I rinsed the chain in the locker with fresh water that drained out by way of a PVC pipe that exited the hull aft. My chain locker was large enough to stow the hose out of the way of the incoming/outgoing chain.