Groups of character class/species/specialty/utility/prominence to upgrade through, in exchange for a consensual character death, when proper XP/AP is accrued? You'd need the proper type of AP judgment, however. For instance, exchanging XP for scenes would fall into the category of more face time, whereas experience with the combat system would be specialization. Or how about a system where the more you contribute to larger plots, the more you work your way up in terms of ritual importance?