There are many many decisions to which political power can be applied, and some certainly impact different constituents more or less, but "in the aggregate" this seems like a good default. At least, I could imagine saying that the burden of proof is heavier for those supporting an uneven aggregate distribution of political power.

One potential problem with this framing is that "political power" isn't separated into "whose goals do we try to achieve?" vs. "how do we try to achieve the goals". I could imagine one arguing that the first part should be evenly distributed but the second should not.