So this is what they've done with 1hander pDIF

[genome]

Yes it looks like it's not uniform distribution, or rather it's a uniform distribution before a hard 2.0 cap is applied like Aurik also mentioned above. In that case even in what looked like the most nerfed area of damage compared to previously (at 2.0 cRatio) the pDIF average is at 1.9 and not 1.8 (as you would expect from a uniform distribution from 1.6 to 2.0), so the damage in the worst case scenario is nerfed at most 5% from pre-update (so VZX your red line over the studioGobli chart would actually be higher).

Another thing to consider is that even in the "bad region" that has nerfed melee damage of up to 5%, your critical damage average is starting to get buffed and is actually raised up in average from pre-patch. So yes you can get as bad as a 5% less damage on your non-critical average, but you also are getting higher critical average, and while your critical hit%, which even without a lot of DEX might still be 20-25%, and the increase in average there is a % over larger numbers so it can probably more than compensate for the damage loss on non-criticals.

The buff you get at cratio 2.4 is very nice and very substantial, sure it's mostly for farming (e.g., helping THFs with relic dagger farm spiders faster...) but the best part imo is still how much this simplifies a lot of tests and gives you a more immediate feedback of how close you are to the cap.
Since the damage change is the same for all 1handers anyways I like the change, I don't think the 5% change will really impact soloing or anything like melee-burning Kirin and such, and the only other issue is the comparison and shift in balance with other jobs that can use 2H, but we already know that something in the current 2H damage calculation was unintentional and will get changed so I'll wait for that before looking more carefully at how those compare now (even the 3pDIF for both 2H normal and criticals seems like it could easily be a bug too, although that would mostly just apply to farming and not xp).
Either way a nerf of 0% to at worst 5% from pre-update damage depending on where your cRatio is probably won't be what makes or breaks one job or another over 2H users (and again this might be partially or fully compensated by the buff in criticals average)

[Alistaire]

Should have made the "red + blue" part of the graph more distinguishable from the red part. Some sort of "blurple" might work better.

You mean like adaman?