There's something you need to learn about everyday reality, and that is that no one can predict which of many competing projects will turn out to be the most useful, rewarding, successful.
The best advice is to learn basic skills that can be applied to any project that comes along, but don't try to choose the single perfect choice, because there are no perfect advance choices.
Another way to say this is with an old saying: "The first casualty of battle is the battle plan."
> What else could be important in my case?
Focus on broad, transferable, general knowledge and skill. Don't specialize too much, because you might specialize yourself out of any interesting occupation.
