Spells and Feats need to have the same mechanics.
Do away with spell levels and just make each power available when a character reaches the class level.
In other words, organize powers by class level.
How about 3 powers at 1st level and +1 power every level-up.
If there are only 20 levels then about 23 powers.
You can use any power as many times as you want in a fight except burst spells which can be used only 1 time an encounter.