Now only you will truly know if C++ is suitable for the tasks you do but unless you work at a university then chances are C++ will be good to great for whatever you need.
"I am already familiar with C, as well as Python, Go, Java and a few other scripting languages."
In terms of relevance in the real world, those languages cover pretty much all bases. The only reason I can see for learning more languages would be to learn entirely new ways to think about programming i.e. different paradigms. Functional programming is fine as far as that goes, but constraint programming is even more radically different (it is not likely to be viewed as simply a "style" of programming that can be used in C or Python), so I mentioned it.