Experienced Devs

Actually, I don't think there is a technology some could recommend that will magically boost your career. Because this will highly depends on what will be required in upcoming projects and no one can know this. So just go with whatever you want and what your interested in.

However, one skill that many technical people are missing is the ability to communicate with other people outside of their own skill spectrum. In my eyes this is the most important thing if we talking about career, because in the end the money never comes from technology it comes from humans and in many cases non technical people decide about you promotion.

So I don't think there is a blueprint for learning such skills, but I guess best thing to do would learning by doing. Go start communicating more with people outside of a technology bubble, try to organize events with other people or maybe even get politically active. Learn to know when people know what you are talking about and when not. Good example would be the use of the abbreviation LOE in your original comment. People seam not to understand what this actually should mean. Here it doesn't hurt much but doing this stuff to often when explaining a concept to a college maybe end up in false Implementation because of misalignment.