A small PVP game that keeps the current AOC PVP mechanics but eliminates gear boosts and cheats -- this is a great idea. Time and time again I hear people say that AOC has either the best or one of the best PVP gameplay controls.
Make it like chess. You got nothing coming in, and you got nothing going out. No saved toons. Just skill.
For variability, introduce new terrains, and different PVP games.