Aquarius: big Pirate boat.(also:made a pirate song)

Piscis: Big oceanic castle (prismarine and conducts)

Geminis:Building a platform for space ships.

Scorpio:Mega floating archipelago

Taurus and Aries: mountain/ volcano (you have to be decent at parcour to access)

Virgo: Underground city (whit villagers)

Capricorn: mega mushroom house.

Leo: Turned the whole mountain into a hive. (changed the floor)

Libra: Made the village more modern.

Sagittarius: Jungle castle.

Cancer: snow/ice castle.

Also:
Have a nice day!