Earlier I wrote about whether or not practicing tremolo is worth the time. My answer was similar to how I approach all my practicing: ruthlessly.
Your time, my friend, is valuable. Your practice time is even more valuable. You’re busy, and that hour or two of guitar each day is hard to fit in. Practice time is so valuable that you have to find the few most effective things and only use them.
Be ruthless with your practice time. Treat it like an experiment: change a few things at a time, cut what doesn’t work, and keep what does. Never stick with a method or an exercise or a routine because an expert (including me) told you it was the best. You are your own teacher and expert in the practice room. Evaluate constantly, take notes, and keep the most effective things.