4th edition rules - Psionic unlimited

[Anaraxes]

Originally Posted by Tinman

You can, if you want to, build it with a costs fatigue limitation.

And further, you can require that all abilities with the Psionic power modifer must have the Costs FP limitation. You might build the first level into the power modifiers, or simply require that each ability add that in (since you might want different costs for different abilities).

Development of more expertise in the ability could be represented by buying off one of the levels of Costs FP, so that more proficient characters spend less energy doing the same things.