I'm glad for the universal DH. I know that not everyone agrees with the idea, but, as cool as it is to see the (rare) big hit from a pitcher, pitchers are usually automatic outs, and I'm sure that NL pitchers (when they pitch) get a stat boost from facing so many weak-hitting pitcher-hitters, so comparing NL pitchers to AL pitchers has been a bit unfair.
Also, having the DH be an AL-only rule has actually been an advantage to the NL team in the World Series, because the NL team, which reached the World Series without the help of a DH, suddenly gets an offensive boost for games in AL parks, whereas the AL team, which relies on the DH, suddenly has to go without one in NL parks. And in order to keep their DH in the lineup at NL parks, they need to put a guy in the field who isn't used to playing in the field. I totally understand where anti-DHers are coming from—the traditionalist "pitchers should hit" and "hitters should field" concepts, and more strategy—but I think that both leagues, at minimum, should be the same—both with DH, or both with no DH. And since I like more offense, I want the DH.
I actually think the inverse has been the case i.e. because the AL teams have a DH slot, they have a much better hitter in that role than the NL teams do and as you say it isn't like the NL pitchers who hit regularly provide much of a boost. So the AL teams have a bigger advantage in actually staffing a DH position, while the NL teams do not staff that position and thus have a random backup in it.
I see your point, and I agree that the typical AL DH is much better than the typical "NL bench player thrown in as a DH"—AL DHs are full-time, and are usually pretty good hitters and/or sluggers.
But I think the issue goes beyond a straightforward AL vs. NL comparison; I look at it from the perspective of relative upgrade/downgrade.
NL teams are used to having an automatic out in their batting order—a pitcher who in most cases is batting below .100, so even if their DH is a mediocre bench guy—say, someone hitting .220 with 8 homers—that's a decent boost to the lineup. But AL teams depend on the DH being one of their best hitters/power guys, so removing his (in most cases) 30+ homers and .260+ average from the batting order is a big blow. They can, of course, put their DH in the field in order to keep his bat, but that's usually going to hurt their defense, and they still have to have their pitcher hit, which is going to force a regular bat out of the lineup—and even if that's a mediocre bat, it's still better than what a typical pitcher brings.
Edit: My opinion on the shift is that it's ugly, but I don't see it being an unfair advantage to the defense. If hitters aren't talented enough to hit the ball to the nearly-empty side of the field—or if they're too lazy to even try learning to do that—that's their problem, LOL.
And how do you draw the line on what a "no shift" defense looks like? Do you say that there have to be two infielders on each side of second base at all times? Because even then teams might still do a "mini shift," in which the two infielders on a given side of the field play way over in one direction or the other.