@g4yvm:
I am assuming we are discussing a Bermuda rig sloop sail plan (jib and mainsail)
A keel stepped mast is more rigid but much less adjustable. You can still move the mast top fore and aft by changing the length of backstay and forestay/jib halyard, but that only rakes/bends the mast, it does not actually move the entire mast. Bending the mast also will change the curve of the mainsail leach when close hauled.
With a deck stepped mast you can move the foot of the mast fore and aft - this is one of the major adjustments in managing weather helm. To get similar adjustment with a keel stepped mast you need multiple mast sockets; some boats have this arrangement.
I don't think it is practical to use the mast track that hmsantrim mentioned with a keel stepped mast; that is intended to be mounted on the deck, not inside the boat.
A keel stepped mast can be almost self supporting depending on materials used; still needs a backstay and jib halyard. A deck stepped mast needs to be supported by shrouds at the sides (I would suggest a minimum of two each side, one through spreaders) and a backstay, plus the jib halyard and an optional forestay.
Using a deck stepped mast with a fractional rig there is a vast range of adjustment available.
For a boat this size you could use 100lb dyneema or similar for the shrouds and stays. Attach the shrouds and stays to the chain plates with fishing snaps. Works great for me.
Using wire stays looks good and allows you to rig the boat pondside with everything going back in exactly the same spot. The downside for me with wire rigging is that it enormously strong and if the boat is blown over while on a stand it is likely to tear the chain plates loose. With dyneema and fishing clips, the clips will pop undone before anything more substantial breaks.. I have had damage a couple of times from the boat being blown off the stand while ashore, I now lay the boat on its side on the grass.... I have never had any damage to the rigging while sailing, apart from a cheap bowsie breaking during a gust. Most damage happens while handling the boat, particularly in gusty conditions.