I know the feeling, as well. But older M&P's do have almost no discernible trigger reset. Even an old GI 1911 has somewhat of a reset, ya know. So while M&P's are pretty soft in the reset department, old or new can be tuned up to do so, if you want.
That is the major reason S&W changed the trigger in the M&P to the "H" configuration. And any older M&P can be upgraded to the "H" configuration, If you can get the following parts(And that's becoming hard to do, as S&W has started to restrict parts sales!); An "H" trigger system, a "Speed Bump" slide lock bar, and either a S&W performance Center sear, or an APEX sear.
Take gun apart, replace said parts, and off you go. A better reset, but still not the "Clack" of a Glock. More so like a good 1911. Which is what I prefer.
Fact is, if you know how, you can make an older M&P have a better reset with nothing more than the "Speed Bump" slide lock bar. It is pretty easy to do. And fact be known, a person can do it using no new parts at all. Has to do with how the trigger bar rides in the frame.
Just thought I would tell you.
Thanx, Gentlemen