Making your game general

ITT we discuss how to collaboratively design our games.

I'm thinking of a seven-part battle royale with prebuilt builds, each inspired on a different planet. Each player gets an abode on a random generated map that he can defend by himself or with follower npcs if his build generates them. For instance one build can have a vampiric sword that drains life and upon hitkill converts not only players but their minions as well.