Yuke is "Rudeus at home". Fighter girl with red hair? Check. Magic girl with blue hair? Check. Elf with white hair? Check. She did not even have green hair, so this is not a true RGB, though, but we can all see where the inspiration was taken from. But besides this it just does not make much sense to me.
He is clearly 2 class: red mage and alchemist. "Red mage" implies ability to use magic, but perhaps it's only buffing - that's fine. Alchemy implies creation of items, at least various potions, and that was clearly confirmed through-out the episode. It was also shown, that his buffs do work, and he also has debuffs like "Snare", that seemed to stop and lift enemies off the ground a bit. He had mana recharge spell, that was called "extremely rare", and he could cook. In what world is that "useless"?
Even if he was hiding all that from his party, he had "students". I won't discuss how he had students at 20 years old, when those students look to be 18-20, as well. But, let's assume he did. It means that he also had renown of his own, and enough knowledge about something, that someone would even want to be taught by him. So, again, how can he be a "teacher" and at the same time "useless"?
I get it, they wanted to show the old party as dicks, not caring for support classes (yet having a cleric, which is kind of support class, as well), but can we please stop showing parties like this? They do not make sense even in games, unless it's a one-time party. It would make even less sense when they are literally risking their lives. Oh, and I just remembered, that he had artifacts, which also increased his value for the party.
This is just stupid.