There's always a couple useless spells around the spiral. Here is my idea on how to fix them
Power Play: Changes: -15% bonus power pip chance (only 20% boost) +15% damage bonus to all schools this would become a risk card, much like berserk/frenzy, but also very rewarding when used properly.
Detonate: Changes: Adds 1 tick to damage over time spells (like the opposite of the cooldown spell) Will still detonate during the next tick, but gets a bonus tick of damage Now targets all enemies -2 pip cost
Cooldown: Changes: Now adds a "tick shield" that blocks the next tick over time by removing 1 tick from that over time
Guidance and Precison: Changes: Now grants accuracy based on pips, but does not consume pips (1 pip = 5 accuracy)
Honestly I think that the balance of it for the level and pips is fine. It's easy once we get higher level to look at some of the spells from earlier days as being 'useless' but they may have had their place and still hold it for lower level wizards. When I was a noob and someone played power play I was so happy lol.