I like to track RPE, and I will frequently make notes about big deviations from my normal routine such as missed meals, buffets, bad sleep, illness, as well as tweaks with my form, notes about pain, and other such tidbits of info. I strongly differentiate between a complete rep and an incompleted rep, and I notate it as such(e.g. 405x10 vs 405x9+1 for a forced rep or assisted rep). I generally dont track calories or macros in my log as such. I also track what I do for warmups/stretching.

Through this, I've really dialed in my form, but I've also learned to catch things before they become issues. For instance, I know that pain in my front hip might indicate impending low back injury. I know certain shoulder sensations or neck issues may be indicative of impingement. And I know if I want to sort of cheat on a max bench/bench PR day, I should load up on carbs; meanwhile carbs dont affect my leg workouts at all.