Ugh. Major edits...
I dunno if this is your kinda thing, but here's one worldgen that might have what you're looking for too,
Terrifying and Joyous available in the same embark with Major river and volcano, in a worldgen with 8192 volcanoes:
World:
http://dffd.wimbli.com/file.php?id=3312Requested worldgen file:
http://dffd.wimbli.com/file.php?id=3327All 3 savage area types are right there:
This map is unembarked worldgen .31.16 stopped at end-year 50, with maximum numbers for titans, megabeasts and semimegabeasts, all races are alive and neighbor the said embark area.
The world was generated with 8192 volcanos, 800 rivers to start and 400 rivers to world finish (to try and get big ones). It has at least one normal 4x4 embark site with a terrifying volcano area and Terrifying/Joyous major river in it, also tropical area with lots of wood. Elephants and alligators confirmed on test embark with feather trees.
The said Terrifying and Joyous embark can be found from the lowest left "World location" screen at coordinates 5 to the right and 3 to the up. at a double side by side volcano lieing on a major river, double blue line, happening to be on a border of Terrifying, Untamed Wilds and Joyous Wilds area. The embark could be made into 2x4 embark, still retaining both areas, the river and the volcano.
This embark has all three Savage area types in one 2x2, if you choose the area correctly. Lower part of river is Joyous Wilds, Upper river, the Volcano and immediate surrounding 2x2 shows up as Terrifying. Right side of river shows up as Untamed Wilds, You can even choose a 2x2 Embark with Terrifying, Untamed and Joyous parts if you forgo the major river and the volcano. Or get them all with a 2x6 area.
This is a rather specific world and area that I had been looking for a long time so I thought I'd share it. Right lowerside of the map is Tropical Moist Broadleaf Forest and Joyous Wilds, left side Terrifying Tropical Freshwater Swamp. Temperature is Hot and I did not spot any flux or gabbro yet, but I'm not picky about stones anymore myself. More of a challenge with no flux.