[dragonwriter]

> It is pointless to look at income in this regards.

Whether or not you subjectively think it is pointless or not, the well-established meaning of “progressive” and “regressive” taxation does loom at income.

If you want to invent your own terminology to reflect the considerations you believe are important, great, but overloading established terminology used consistently by people with varying normative beliefs about the subject matter to mean something completely different because you don't like the way it maps terms on to facts isn't helpful in communication.