I have only 2.7-2.8k discoveries (active ms), but maybe it will be useful for someone:
NATURAL- Route 119A - Cacnea, Nincada, Shroomish, Skorupi (Fled = Ferroseed)
GLACIAL - Route 10 - Wailmer, Spheal, Clauncher, items: Rare Candy, Fresh Water (Fled = Bergmite)
FERAL - Fiery Path - Cubone, Zangoose, Houndour items: Repel, Escape Rope (Fled = Mawile, Absol, Noibat, some fossil smashed)
HISTORICAL- desert - Makuhita, Throh, Sawk, Tyrogue, items: Ultra Ball,
HAUNTED - Rusturf Tunnel - Duskull, Shuppet, items: Escape Rope, Repel, Rare Candy,
MINERAL - Route 115 - Nosepass, Onix, Drilbur, Aron, items: Fresh Water, Escape Rope, (Fled = Beldum)