I agree with keeping this thread going, and one of the best ways is for me not to respond to everything, so I will tackle a few of the spells.
Through some testing of my own, I found a couple of bosses the Fire spell can be made to be useful for. My current complaint is its current design. It's a tiny fireball. A complete mess. Nothing ferocious when you think of fire spells in general especially if you compare it to the spells from A Link To The Past. The Fire spell doesn't have to go. Redesign it to make it more appealing. Also make have to be used against some bosses.
I think the jumping higher should be replaced with a mid air jump. That would be much more appealing and would fit better than just jumping higher. And combining that with the Dash from Shadow Of Night, and you have a total winner. I know the mid air jump would require a bit of coding to get correct.
Spell spell has been absolutely useless. You don't need the Magic Key to beat the last 2 palaces or The Great Palace, so taking the time to even use the Spell spell to get the Magic Key isn't necessary. Replacing that spell with something new would be best. A Freeze spell or Njosro's Ghost spell would be a couple of good ideas.
Let's here some other ideas.