Wyoming (the least-populous state) has .183% of the US population, so it should have .183% of the US House seats if they were fully proportional. It actually has .230% (1 / 435)--about 1.25× the power it should have. Rhode Island getting two House seats gives it about 1.34× the power it should have. Montana having only one seat leaves it at about 0.673× the power it ought to have.
As quantization errors go, the House's quantization isn't terribly distortive.
The alternative view is that CA, MA, and NY already get a Democrat candidate 95/270 or 35% of the way to the Presidency with just 20% of the population. Do those states really need a greater impact?
"Fair and just" is out the window as soon as others get to decide how the fruits of 40% of my labor gets spent without my consent. At this point, we might as well just change the rules as we go along because you can't really point to the system we have now and say "it's fair" or "just" in a 100% clearly defined and unambiguous sense that we can all agree on.
