Lanefan
Victoria Rules
I'm defining fair as meaning that a character played for 6 sessions should level up where a character only played for 3 of those same sessions as a replacement for another character who died 3 session in should not, as it's unfair to the character who was there for all six.Why is it not fair? How are you defining fair? What's it to another player if the new player starts at the same level as the party? Does that invalidate the fun that was had at previous games?
Levelling is not a reward for players sitting at the table, it's a reward for characters in the fiction.