Fighter, Barb, Pally, advanced patience tuts, give them something to read while they get buffed, grease...and the good stuff shaken not stirred.
Clerics, whom to heal, sp management
Looters, how to link gears into chat window, show them the DM typing ignore
Lemmings, gear degradation, ability drain, xp loss, neg levels, any packed trap effect
Arcanes, targeting, a 3minute session with a 60reflex/evasion kobold, and only niacs available, then they can get mm or remove kobold, spawn a caster with puny saves. Also dismiss charm tut!.
Rogues, basic stealth play, trapping, maybe some acrobatics to reach a lever before a barb hits sprintboost and get it.

If everyone only learns whom to target, when/where to take cover, getting prepared before a bigger/any action and the basics, it is already good.

Korthos quests basically encourage the "tap forward button and hold attack" playing. They should require much more strategy and cooperation to pass these tutorial quests.