Schizophrenic Noble Challenge:
Make a table of achievements, goals, and aspirations. Optional: Make a second table of limitations and guidelines.
Roll randomly on table(s).
Every year, roll another die- on result of A-B, continue; on result of C-D, the mad king in charge of this operation changes his mind, and you have to reroll. If you get the same result, it has to be radically different in some fashion. Tailor results to make king/noble as stable or arbitrary as desired.
EXAMPLE:
6-sided die:
1 Cathedral
2 Mausoleum
3 Selectively bred livestock menagerie
4 Invincible army
5 Museum of Fine Crafts
6 Statue army
4-sided die:
1 Must use precious metals
2 Every dwarf must contribute directly
3 Population cap/quota
4 Completed in Armok-forsaken wilderness, glacier, etc.
You roll a 1, Cathedral, and decide to add a limitation, rolling a 3, population cap/quota. We'll say you prefer small forts, so this is a quota- clearly it's not a proper cathedral if there's any less than a hundred dwarves to appreciate it. You want the king to be fairly stable, so you give him a 10% chance to abruptly change his mind.
Next year, you roll the chance. If it happens to be that 10%, you roll again. If it's a cathedral again, you'll have to build it overlooking the lake instead, or it has to be of diorite, not marble! If you roll something else, he's completely changed his mind and now wants you breeding horses and giant eagles for some reason. Cathedral? What cathedral, the king wants his horses! Unless you reroll cathedral again, of course, or maybe you can treat each new request as "in addition to" rather than "everything you did was wasted, do this now!"
Of course, random tables are my first reaction to a lot of things.