These are just a few thoughts off the top of my head that keep me coming back to the game:

1) Show consistency. It's one thing to say you 'are' this type of character but another to show it over and over again.

2) Let your balls (or in the case of female characters 'ovaries') drop. I love nothing better than an outstanding fight. I'll generally reward well for watching one also. Personally, it keeps me coming back.

3) Players (nor immortals) are not entitled to more. We all should be playing this game because we enjoy it. The moment a reward or a perk belittles your experience I encourage you to consider why you are playing this MUD.

You want my attention as an Imm? #2 will do wonders. Let em drop!