One of the unfortunate rules of this particular plane of existence is that you can't change what is real merely by having contempt for it. So in keeping with the Whether You Like It Or Not Doctrine, you should know that the designated hitter is eventually coming to the National League.
The NL, of course, has never used the DH except in road games against AL teams. The AL, meantime, has used the DH since 1973, but there's increasing momentum for the leagues to have uniform playing rules. That's why the NL is going to adopt the DH, likely in time for the 2022 season. Fans of a traditionalist bent of course don't care for this. Even though pitchers are bad at hitting and gradually getting worse -- they're selected for their pitching skills, not their hitting -- a sizable demographic of fans loathe the idea of the DH in the NL. (This is despite the fact that an NL president first formally proposed the rule back in 1928.) However, the DH is used in pretty much every other level of serious organized baseball, and owners are becoming more and more hesitant to see their expensive hurlers risking injury on the bases and otherwise boring the hell out of everyone at the plate. The DH is coming to the NL whether anyone likes it or not.
So proceeding from that firm assumption, let's concoct a compromise solution that will make everyone slightly mad but at the same time make DH bitter-enders slightly less mad than would the full onset of the DH era in the National League.
The big idea? The home team of a given game gets to choose whether the DH is used.
That's pretty self-explanatory, but just in case it isn't we'll drone on about it. Before every regular season or postseason game, the home team will declare whether the DH rule will be in force for that particular game or whether pitchers will bat. There would be some sort of cutoff -- say three hours before first pitch -- at which point the home team must make its choice. The decision affects that game and that game only. If a given home team picks the DH rule for one game, they're free to keep the DH for the next game or choose to have pitchers hit, even if it's a twi-night doubleheader (remember those?). Teams will not be allowed to make one-game roster tweaks based on the home team's decision, which means they must structure their roster to account for either possibility and be subject to the usual limitations on roster churn.
Now let's roll out some examples. Let's say the Astros are at home and have a somewhat unsettled DH situation. Zack Greinke, who's a quality hitter by the standards of moundsmen, is starting for Houston. Visiting will be the Twins, who boast ageless slugger Nelson Cruz at DH. Starting for them is Jose Berrios, who has a .343 OPS in 15 career plate appearances. That's advantage Greinke at the plate, one assumes. So the Astros choose to have pitchers bat for that game because doing so forces the Twins to make a difficult decision. Does Minnesota manager Rocco Baldelli put Cruz on the bench and hope that a high-leverage pinch-hitting opportunity comes his way, or does he scramble his usual lineup and stick Cruz in an outfielder corner (or perhaps at first base) in order to keep his bat in the lineup?
On the other side, maybe the Diamondbacks are visiting the Red Sox in interleague play. Madison Bumgarner and his 19 career home runs are on the mound for Arizona opposite Chris Sale, who's has a career slash line of .120/.120/.160 at the plate. In order to keep the D-Backs from having that big advantage in terms of the No. 9 spot in the lineup, the Red Sox choose the DH, which of course allows J.D. Martinez to be in the lineup while not having to put a glove on. MadBum, meantime, doesn't get to take aim at the Green Monster.
This format would dovetail nicely with the new roster rules in place. Teams will be allowed 26 players on the active roster for 2020, and it's widely expected that MLB will soon announce that pitcher spots will be capped at 13. That extra roster spot means teams can sit a primary DH when necessary without being overly handcuffed. As well, this adds a layer of strategy to each contest and a new basis for evaluating a team's decision-making.
There's a counter-argument to be made that this might lessen the value of DH-only players on the market. That's certainly a possible consequence, but also consider that NL clubs under these rules would be seeking out and paying for better hitters in order to be DH-ready. That should provide a balancing-out effect. As well, the reasonable expectation is that teams will most often choose to use the DH, which should limit how much DHs are discounted on the open market. There aren't many pitchers who truly stand out among their peers at the plate, and that fear of injury on the bases is noted above.
Effectively, this likely puts the DH rule in place for the healthy majority of MLB games. However, it doesn't completely do away with pitchers' batting, as teams on select occasions will surely go that route. Even if pitcher performance at the plate continues to degrade and the data sample is whittled down by adoption of this rule in the NL, you'll still probably on occasion get a home team that wants to put an elite-hitting opposing DH on ice for a game or three. In that sense, this rule would help pitchers survive as hitters, albeit on a much more limited scale than what's currently in place in the NL. Sometimes having pitchers hit will make tactical sense for the home team (especially if more two-way players like Shohei Ohtani make their way to the league), and pitchers who do relish hitting will be free to lobby their managers in advance of their home starts. It also adds that strategic element to every game over and above the usual lineup decisions.
No, you are not happy with this compromise solution, which is why the word "compromise" is being used. If, however, you go beyond merest unhappiness and instead have rabies-grade scorn for the idea of the home team deciding whether the DH will be used, then delight in the knowledge that this will never come to pass.