I wouldn't dismiss them straight away. If you think about it the 4 fluke folding is a very stable design. It will always find purchace whatever way it lands on the sea bed. Whereas the old fisherman is fairly unstable and has to hit the bed the right way up. Likewise for plough,bruce and CQR types, very easy for them to fall over.
My little anchor holds my boat firmly in most situations where it can get down to the bed. Weed can be a bit of a problem for it.
You can get some plastic chain from B&Q (Castorama) well proven in the sailing world. It is often used for garden fences and keeping small dogs under contol. This type of chain is hollow to keep the weight down, but if you drill a small hole, say 2mm, in each link, then when it is deployed the links will fill with sea water and give you the catenery effect you desire.
Quite a simple answer really, I'm surprised you didn't think of it yourself. Keep the chain in the chain locker at the front, the windlass at the back and the anchor in the middle. This way the weight will be evenly distributed.
The plastic chain works well, apart from when getting the anchor back on board, when a stout rope, attached to the crown of the anchor, provides the necessary reassurance.