I dont think there is a way to know which one thing in the list of potential 1000 things, will be the one that has highest payoff. And the definition of payoff also depends on what your goals are. For examples, learning computer networking concepts will have different payoff for someone who wants to get a PhD in Machine Learning (it will help him/her write better software maybe, or add to his/her list of employable skills), vs someone who is building distributed systems. So you have to take some bets. Think about stuff like what one or two things you can learn in next 6 months that will get you closer to your most coveted goals. And just try to focus on them. If there are more than 1/2 things, filter them out based on what gets you excited more. At the end, its all about your perspective.