Dice involved battles can be fun, if not a bit lacking in creative. For instance, you may see aviable dodge but a dice roll could dictate you have to take a hit. 

A former Mod on Guild made one, that involved hit points, where dice rolls dictated of you got hit and how much NO you lost - as well as how much you had and how hard you hit anyway. I tested it out with him. #OldGuild. 

A PW/MV would be nice as well, provided it was done right. One I participated in on MYB before coming to Guild was more a gathering of different threads/people in a loose storyline compared to having an overall one. We simply made and built characters. In the arena, it would have to be different obviously, with the fighting being more centric.