Alan:
I'm torn. The idea of "frequent player miles" is kind of interesting, but I don't play enough other kinds of games to know how this works in the gaming world. I've seen a lot of websites - like those of talk show hosts -- which do have "insider" perks, although it usually requires a monetary support fee. In lieu of money, it might be nice that registered players get special recognition or rewards. However, there might be a way, however, to give everyone the chance to know about it, that you could indicate that on the front page where all players can see -- "bonus points" for members.
Cheers,
3-B
And Viz -- maybe you could make some wine out of those sour grapes!