I'd recommend reading the part about enforcing existing rules to those in favour of gimmicks that change the way the game is played.
I'm strongly in favour of enforcing the one foot in the box rule, reducing mound visits, and fixing the replay system.
If those don't work, I'm somewhat open to strike zone changes (though I don't think the proposed changes will help or be enforced consistently) and some sort of way to make pitchers speed up (no leaving the mound, automatic walks, fewer warm-up pitches).
I'm strongly against gimmicks like this 2B rule. It's like the shootout in hockey, as BTS mentioned earlier. We can make the game faster without stupid things like this.