Another thing: If you can get your hands on a map (or, better yet, a Magic Map from the Twilight Forest), you should be able to see much farther than even the "Far" rendering distance will allow.
If I'm not mistaken, the Magic Map has longer range than the vanilla map. Harder to get if you've never been to the Twilight Forest, of course, as you need Glowstone as well as two TF items...
I've created a magic map centered on spawn in my current test world, with Plenty o' Biomes enabled...
That's more ocean than I thought there was. Even flying around with full a MPS flight suit, it's a big ocean. I'm not entirely certain how much continent (or ocean, for that matter) isn't shown on this map.