I always liked the Dragon Cult a lot as flavor- and mechanicwise it is very different to a normal religion. That's why I consider it good that Orbis reintroduced it after its removal from basic FFH. But the reason why it was removed nevertheless is still valid: It does not enough to justify much effort. Also you cannot really control its spread even if you want to spread it (with the Kuriotates or the Sheaim). The only use it usually has for me is to grant me Spiritual if I play a Sheaim or Kuriotates minor leader, but IMHO that should not be the main use.
I had an idea: Sheaim and Kuriotates get an unique ritual that randomly spreads the Dragon Cult into cities that don't have it AND all non-Kuriotates, non-Sheaim cities that already have the dragon cult will get a temporary malus (like unrest, riotturns, destroyed buildings, research turns lost, units turned barbarian etc.). This way the Dragon Cult will finally be the annoyance it should be, not something that you can ignore the whole game (as it does nothing). You could give the Kurios and the Sheaim different rituals with different results (as the worship for Abashi and Eurabatres should be quite different), but the main idea stays the same.
I had an idea: Sheaim and Kuriotates get an unique ritual that randomly spreads the Dragon Cult into cities that don't have it AND all non-Kuriotates, non-Sheaim cities that already have the dragon cult will get a temporary malus (like unrest, riotturns, destroyed buildings, research turns lost, units turned barbarian etc.). This way the Dragon Cult will finally be the annoyance it should be, not something that you can ignore the whole game (as it does nothing). You could give the Kurios and the Sheaim different rituals with different results (as the worship for Abashi and Eurabatres should be quite different), but the main idea stays the same.