I see a lot of people are misunderstanding this thread.
The main idea was to give a use to Colosseum and School of Magic to make them look more active to the adventurer's eyes.
Skill ups was just one of the many ways that could be done. I am not looking for easier skill ups^^ Like I said it could also be a place where to earn scrolls, or something else if you can actually post other ideas rather than keeping saying skilling up is already easy. I know it is, and this is why this topic is not about easier skill ups.