The one thing I usually do is get Shadow to not learn any magic. He does miss the bonuses, but with offering + genji glove with 2 good swords in the Colosseum he will only fight.

For magic, I always give the strong magic users tier1 esper priority then everyone else. I dont split the magics based on type since it reminds me of previous versions. Everyone should know cure2 and be able to resurrect/heal the party if it happens that they are the last one standing in a battle.