Is the Standard Model a Good Theory of Physics?

The current best theory of physics so far that we're pretty sure is wrong and needs to be updated ASAP. The standard model has all the particles we've been talking about, but there's also a shadow particle for every single one. Even if there weren't questions about dark matter and gravity, just zooming in on the particles that we do know about, there are lots of questions that we don't have answers to. So you can look at the standard model and you can say like, why is it this way? And also, does it actually explain everything we see?