Yeah I actually completely agree with you, I was unsure on the island format but since I was going for the pirate theme I just went for it (and if it replaced another island map as you suggested you wont see me complaining)
On your second point I know there is a lot, its about 40% water, but I felt if I put too many islands in the water it would have looked wierd so I just went with it and hopefully it wont deter too much from the map, I feel it will be fine as it will be very easy to see where people are if they are out swimming in the water