Unfortunately, none of these skill checks will stop the problem because it won't stop someone from passing said check then spamming skill 1, only using ice spells, watching netflix, etc. You can't program your way out of bad player behavior. Can the skill checks be useful? for some yes, as a gate from deliberately bad playing? no. It could only stop those that are legitimately bad at the game and I don't think there are many of those to be honest.