DFHack for fixing diplos, renaming things/squads and other benign uses only.
Try a good region next to a necromancer tower (for fun, undead gnomes or unicorns?) and implement specific goals/restrictions, such as each pit-mining only, or each player must undertake a project, either useful or decorative, potentially above-ground only OR finish a previous players' project. Or make the fortress a giant industrial farm, with high-density animal populations (must have both grazers and egg layers) and focus on cheese production and leather and bone crafts, maybe only export animal products, with farming being solely for booze and clothing. Maybe mandate the capture of a necromancer and creation of a undead zoo.
Or if you're really crazy, insist the game embark on an aquifer.
Like those ideas?