I'm glad I found this thread and I'm thankful for all that your putting into it . I'm only about halfway through reading everything you have so far, but I have a quick question/suggestion:
I agree that Spell Casters should definitely be hindered by fear, but what made you decide to do Spell Failure over a Concentration Check/Penalty or something else.
Edit: Looking back over Panicked in the Player's Handbook glossary, I found it odd that it states "[The subject] can't take any other actions" but then states that they "can use special abilities, including spells, to flee." I don't like that (and, thus, like your adjustment a lot better) because that means the wizard can just whip up a teleportation spell and get away easily .
I also might recommend spoilers for the Spells/spell lists.