So, here's a question: How many XP does a hero need before they become too powerful for any reasonable threat? It takes 180xp to take a 2 point skill to a 6 point skill (about 4 adventure's worth), so if this is a weapon skill, an adventurer can have an effective combat skill of 13 in relatively short time (skill 7 + weaponskill 6). I know there are plenty of ways to deal with that (magic, social situations, making them lose their weapon), but when does a Director have to start making convoluted reasons to bring characters down in power?
An elf wizard with maximum magic (8) and 2 points in wizardry can choose 20 points worth of spells, have 20 magic points and can use 5 lightning blasts a day. 180xp can increase magic by 1 or it can increase wizardry to 6 so that if the elf has the natural mage talent (and what wizard doesn't) then they can automatically succeed at lightning blasts. They also have 16 points worth of spells that can deal with almost any situation. However, this also means that they have 10 stamina points at most or 5 skill points, so it's probably easy to take them out.
So how many XP does it take to make them unstoppable? 500? 1000?