@Ashrem How about something like these spaced out with other stuff and as you say some being on the daily line:
Research or upgrade L12 prize nut factory
Gain 3 enchantments prize 10 nut butter
Have L2 nut factory prize nougat
Scout 1 province or upgrade L12 prize fondant
Have L3 nut factory prize 5 special nuts
Pay 1 harvest cake prize super cool building
The upgrade to L2 nut factory uses 5 nut butter, upgrade to L3 uses the fondant, L3 unlocks the production of harvest cake and it requires the ingredients 5 nut butter and 5 special nuts and takes 24 hours. If the L3 nut factory was also a useful building then it is also a reward. Perhaps it could be worked like most regular factories but gives some culture and has productions for things like orcs or mana.