this Seed is done with certain options for it to work right deselect Find Balanced Seed and pick large Biome Size. Not sure if the name of the map affects the generation but just encase I called mine Best Island Survival Yet I typed the first letters in capitalized. this Seed i made is Large and the inner 3x3 maps are %90 island survival the best i have seen yet, still looking for a Large seed %100 island survival the out maps around the 3x3 are %75-85 water tho it is really close to %100. Yes Find Balanced Seed and Biome Size greatly affects the seed even if u type a seed in and\or leave the seed blank (to find a random one).
Spawn: -192, 67, 128
End Portal: -960, 47, 50 (under water floating room just off an island)
Library: -928, 14, 28
Ocean Monuments: the 2nd & 3rd ones might be same one lol sorry (3 to 4 OM's in first map u start in wow)
Blaze Spawner: in the nether of course (note u don't have to have a nether map to use cords in nether, u can use any map just only nether map show u the nether tho)
57, 71, 146
The island u start on has no trees but south u will see a small to medium isalnd with a tree, bonus chest comes with a jungle tree sapling (for those that don't know Bonus chest aren't random don't believe me check for yourself), sugar cane is on an island close by. Animals spawn all over these islands. The 2 or 3 big land masses on the outer parts of the large 5x5 seed haven't been explored but seem to have a varitey of biomes.
The nether fortress isn't too far from either island but for some reason where i put it, it brings u back about 100 blocks away a long run, I only found 1 blaze spawner and if u place the nether portal in normal world at 246, 65, 1165 to 1168 you will be in front of the blaze spawner, remember you can go in on peaceful and build walls and a spawner farm then go back in too normal up to hard and still get achievements and trophies difficulty don't affect the trophies.
If anyone can find a better IS Island Survival please yet me know? (remember u start in the center of a 3x3 area %90 island survival)
Still looking for that %100 Island Survival Seed please help.