Hold on. Hear me out.But I doubt common players would actually accept to lose control of their main character...
Belonging to someone's clan in a Freelancer-esque mod.
You start out as a nobody. You swear allegiance to a lord and serve as his foot soldier. You become a captain and he starts giving you quests like scouting an area with some low-tier troops you can pick from his party. You rank up, and you get gooder missions and can bring betterer troops. Rank up even more and your lord allows you to sit in his daily court sessions. Once you're trusted enough you can influence him to make certain decisions. After a long service he lets you hold one of his villages, becoming a minor clan with the right to lead your own party under his banner. Then you betray him in battle, chop his head off, and impregnate his wife and daughter as revenge for giving you so many quests to collect butter for his fat army.