Summary
These suggestions are meant for future use on at least one new faction that works well with Special Weeks
Special Weeks would be introduced at v2.2 pre-D

Important: i've not tested v2.2 pre-D yet, as it is in Closed Beta, which i don't have access

Stargazer Ability
Affects Units
Units with Stargazer Ability receive more powerful effects from special week

Wayfind Skill
Affects Wayfinder Heroes
Heroes with Wayfind has Stargazer Ability, more Health and also an Aura which grants Stargazer Ability to nearby Allied Units
Extra ranks increases Health and Aura Radius

Foretell Skill
Affects Foreteller Heroes
Heroes with Foretell has Stargazer Ability, more Mana and also applies a temporary Boost which grants Stargazer to nearby Allied Units whenever they cast a spell
Extra ranks increases Mana and Boost Duration

Twelve Houses Building
Affects Towns
Towns with Twelve Houses Building receive more powerful effects from special week, and earn 100 more Gold Income