I haven't tried fortress mode, but here is my seed. It has several small lakes, a big "sea" with a largeish island in the middle, a volcanic island, many civs, one is on the island, and a large "haunted" area. I started an adventurer near the sea, and everything he had on was made from shark leather. badass...
Created in DF v0.28.181.39b.
[WORLD_GEN]
[TITLE:MEDIUM]
[SEED:4116048886]
[HISTORY_SEED:142041881]
[NAME_SEED:3214122448]
[DIM:129:129]
[END_YEAR:1050]
[BEAST_END_YEAR:200:80]
[END_YEAR:1050]
[REVEAL_ALL_HISTORY:1]
[CULL_HISTORICAL_FIGURES:0]
[ELEVATION:1:400:401:401]
[RAINFALL:0:100:200:200]
[TEMPERATURE:25:75:200:200]
[DRAINAGE:0:100:200:200]
[VOLCANISM:0:100:200:200]
[SAVAGERY:0:100:200:200]
[ELEVATION_FREQUENCY:1:1:1:1:1:1]
[RAIN_FREQUENCY:1:1:1:1:1:1]
[DRAINAGE_FREQUENCY:1:1:1:1:1:1]
[TEMPERATURE_FREQUENCY:1:1:1:1:1:1]
[SAVAGERY_FREQUENCY:1:1:1:1:1:1]
[VOLCANISM_FREQUENCY:1:1:1:1:1:1]
[GOOD_SQ_COUNTS:25:251:503]
[EVIL_SQ_COUNTS:25:251:503]
[PEAK_NUMBER_MIN:12]
[OCEAN_EDGE_MIN:1]
[VOLCANO_MIN:3]
[REGION_COUNTS:SWAMP:260:1:1]
[REGION_COUNTS:DESERT:260:1:1]
[REGION_COUNTS:FOREST:1040:3:3]
[REGION_COUNTS:MOUNTAINS:2080:2:2]
[REGION_COUNTS:OCEAN:2080:1:1]
[REGION_COUNTS:GLACIER:0:0:0]
[REGION_COUNTS:TUNDRA:0:0:0]
[REGION_COUNTS:GRASSLAND:2080:3:3]
[REGION_COUNTS:HILLS:2080:3:3]
[EROSION_CYCLE_COUNT:250]
[RIVER_MINS:100:100]
[PERIODICALLY_ERODE_EXTREMES:1]
[OROGRAPHIC_PRECIPITATION:1]
[SUBREGION_MAX:2750]
[CAVE_MAX_SIZE:25]
[MOUNTAIN_CAVE_MIN:25]
[NON_MOUNTAIN_CAVE_MIN:50]
[ALL_CAVES_VISIBLE:0]
[TOTAL_CIV_NUMBER:20]
[TOTAL_CIV_POPULATION:20000]
[PLAYABLE_CIVILIZATION_REQUIRED:1]
[ELEVATION_RANGES:2080:4160:2080]
[RAIN_RANGES:2080:4160:2080]
[DRAINAGE_RANGES:2080:4160:2080]
[SAVAGERY_RANGES:2080:4160:2080]
[VOLCANISM_RANGES:2080:4160:2080]
going through the legends, it looks like the elves had quite a bit of problems, I haven't been able to determine, but there was a tremendous growth spurt followed by mass killings. You'll see in the history that most elves were killed before reaching age 10. I haven't investigated this further, but it looks like the humans and dwarves lived mostly normal lives.
edit: just realized this was genned in 39b. I don't know if the volcanic island still exists in the latest version. I'll re-gen this one.