Earl, The 14 gallon bin does not have the hose hanging below to connect the barrel like yours does. There are clamps on 2 sides that actually pull the bin up tight against the bottom of the base (there is a gasket there) so that the wheels on the bin are off the ground. When it is time to empty, you simply release the clamps to lower it to the ground and roll it out.
I thought about putting the various shop vac style nozzles on the ledge base. That looks like a good solution. I still may make some holders to organize them. I have been thinking about hanging the hose on the back of my cart similar to what you did on the wall but I need to make sure that extra weight hanging on the back does not make it more likely to tip backwards or require it to sit so far out from the wall (in its currently location) that the front legs become a tripping hazard. I like the idea of a reel but like you finding a place for it is going to be tough. The Fastcap Super Reel sticks out about 23" from the wall. One idea I am playing around with is to hang it on the ceiling but then winding it up becomes difficult so I am trying to devise a way to use a rope or something, similar to how a chain hoist works, to wind it up. I can't seem to find an example now, but I have seen a pulley design that uses a knotted rope to engage pockets around the rim of a pulley like a chain to turn the pulley. I suppose I could just use a rod to turn a crank similar to how a steam locomotive converts linear motion to turn the wheels but that might be a pain and slow. Another idea is to have a spool on the side with rope that winds up around it as you pull off the hose. When you want to wind the hose you just pull on the rope but then you have a piece of rope hanging down that might be in the way. Just sort of throwing ideas against the wall (or ceiling) to see if any of them stick.
--Nathan, TX. Hire the lazy man. He may not do as much work but that's because he will find a better way.