To address the frustration due to grinding, a subtle mechanic is introduced. Early in the game the attributes at the bottom of the upgrade screen are locked, so that the faith and hope are used for tower unlocks. This should prove more effective in making fast progress. Once 4 towers are unlocked, the attributes are presented.
Audio minimum value now completely mutes the sound
Fortune God power now has a cap of 25k gold. Without it, the fortune power was game breakingly OP (thanks to @Voyle and @Lord Failure for pointing this out in Discussions)