The changes to the merit weapon skills are a good compromise (and in fact a better change than simply increasing the category max by a few points), and I will explain why:
As Motenten listed out, it means that under the new system, a 1/5 WS (65%) will be nearly as strong as a 4/5 WS currently is (68%). There are exceptions (Particularly Tachi: Shoha because of how powerful a SAM's other WSs are), but this means that a level 1 weapon skill will almost always be useful now. That extra 20% mod is admittedly quite a bit, but I don't think a lot of you are understanding what the idea behind the adjustment is.
Now, the vision the devs initially thought of (That we can choose between being versatile or being specialized) is actually true, because now even a level 1 weapon skill can be quite useful. As someone who plays a great variety of jobs, I greatly prefer this change over them simply adding an extra 5-10 total levels to the merit category, because now players can pick and choose. Beforehand, investing 1 point into a weapon skill would be completely useless. Now, most of the merit WSs will outdo most non-REM WSs with a single point invested.
Granted, it would be cool to have both this adjustment and a raise to the cap, but people are really exaggerating when they say that you are choosing between having 5 weak weapon skills and 1 strong weapon skill...that was true before. Now you are choosing between having 5 good weapon skill, 2 great weapon skills or 1 amazing weapon skill etc. It's far more flexible than it used to be.