Candy Wrapper - wrap a selected candy which explodes immediately, giving the combination power with other special candies.
Booster overcharge - using boosters or specific quests to charge a meter which over charges the boosters into more powerful versions for a limited time, like the double colour bomb.
For example, the lollipop hammer has a 3x3 effect or can completely remove one obstacle. The UFO could fire an extra 3 striped candies. Using the party bomb gives a random special candy after every turn. Free switch can swap any 2 candies on the board and the striped brush can create the striped and wrapped candy combined effect.
Even if only one overcharge can be used per level to balance it out. Just a few thoughts I had, and thought I'd share. 🍬