The best bow deflector I have seen so far is Nohuhu's on his Kahikolu boat(batboat) Here is a link ( http://www.hobiecat.comwww.hobiecat.com ... 2&start=15
My opinion this design helps deflect waves coming over the bow, and provides lift if the bow dives, but is soft and only sticks out in front of the boat a tiny bit (would actually fit nicely under my bow sprit).
With my foils even when they are not engaged they do make a little drag (more when they are engaged). Actually I didn't put any of the foils on my new boat, and have not had a problem yet. I think I am going to fashion something like what Hohuhu has.
One problem I do have is because I have so much sail area, if the bow does nose dive it doesn't come back up again (what I call nautilus mode), that why I made the foils in the first place, I think Nohuhu's design would eliminate the need for the foils.
The way I plan to make mine is to go to walmart and buy a large white cutting board (1/4 inch thick x 12" x 18" or larger). They are white HDPE polyethylene and very strong. I'm going to cut a V shape out that fits around the bow. Then use a torch or heat gun to heat the cutting board while it is sitting on the side of a barrel (like a 40 gallon metal barrel, or whatever I can find that is similar), once The PE heats up it will conform to the round shape making a nice bend pointing downward at the back. I would then contour the outside to follow the hull shape and make it look nice.
On my boat I would just trap the deflector under my bow sprit. If I didn't have the bow sprit, I would form a piece of aluminum (1/8" thick x 6 inches long and 2 inches wide) with a slit in it to fit over the front lifting lug, then put a key or pin under the lug that traps the aluminum (holding the aluminum down). Then screw the polyethylene onto the aluminum (with stainless flat head screws). No modifications to the boat itself.