I always like the island seed 23998886688. I dont remember who posted it originally but it is pretty awesome with the new biome scale bar. If you load it on large world size and large biome size you get a lot of water even on the other maps. Not to mention a massive group of mooshroom islands. I haven't explored all of the maps but i have seen many ocean structures as well as some large land masses on the outer maps. Anyway, check it out and if anyone knows who posted the seed first let me know so i can give them credit.