The more you raise the windlass above deck--the more leverage the
winch exerts over the deck itself. This means the heavier must be the mountings and the more extensive they need to be. I think there is more problems in raising the windlass than using a slightly larger diameter
anchor roller.
By the way--if you use a kellet (angel) you may get away with a less weighty anchor--and thereby solve some of your problems. I use a 60 lb Manson with a 20kg kellet and have never moved when at anchor. Makes for restful sleep.
I do not use a chain stopper to hold an anchor chain when at anchor. I only use it, if it is there at all, once the anchor is at rest in its lodgement, preventuing its accidental deployment while the windlass capstan is in use for hauling ropes etc. Once the anchor is aboard it is just as easily secured with a lanyard to a ring bolt or cleat..less damaging to the chain and inexpensive.
For securing the chain (I prefer an all chain
rode for shallow anchorages) I use a nylon snubber sheathed in flexible PVC to avoid chafe and fastened to heavy duty heavily backed deck
cleats mounted either side of the bow. The snubber fastens to a spliced-loop
bridle through-hitched over these
cleats to spread the shock load. If one end comes adrift for any reason the other may still hold. The other end is a chain-hook which slides onto the links. So far it has never slipped.
The windlass is only for lifting the anchor and the snubber takes the strain of any surges and transmits the strain to the
hull and deck through the heavy deck cleats, which can also in a streel boat be bedded on a plate welded to the deck shelf. They can never be too strongly mounted.. If one ever needs to tow another vessel--one need not be concerned about the strength of the deck cleats on the bow or stern quarter. They will always be adequate if properly mounted in the first place.
The windlass needs to be mounted as far aft as is practical with regards to chain stowage and sail handling in the bow. Anchor, windlass and chain locker are heavy. The further aft they are, the longer is the length of chain on deck--and the easier it is to
work on it, but the more of a hazard it becomes to those working
sails. A hawse or spurling pipe solves this problem in larger vessels. Perhaps something to consider..
The further aft all of that weight is, the more
hull buoyancy there is to support it, and the easier it is to trim the vessel. It is far easier tio add a bit of weight to the bow of a vessel using tankage ior ballast than it is to get rid of it if the vessel turns out to be bow-heavy.
All of this is stating the obvious--but sometimes back to basics when making important decisions is not a bad ploy.