[PK]

While I agree with your summary of the issues, I don't think this is the best approach. After all, GURPS doesn't give a genius less of a price break for Requires IQ Roll than an average person. It seems kind of wrong to make a person who pays to buy their FP up really high also pay extra on any powers that costs FP. It's kind of like double-charging.

After all, if I have an ability that costs 2 FP per use, and then I buy FP 30 to compensate for that, I'm hardly working the system. The only time a real problem comes up is if you let someone buy FP 40 and then take "Costs Fatigue, 16 FP, -80%" on 500+ points' worth of abilities. Because of that, I recommend just capping how many levels of Costs Fatigue you can take (I cap at 4 levels, but give double value.)