I think that there is very unconvincing evidence that caffeine causes weight gain, and I get very tired of the constant "stress = cortisol = fat" garbage.....
Our bodies are MEANT to handle stress, and most of what we handle is child's play compared to our ancestors or most animals. Constant stress is bad, but that is a psychological problem, not a physical one. If you live in this country, have internet to read this and a job to afford the bill, you are doing better than 95% of people alive. Be happy.
My N=1 is that I have been a caffeine drinker my entire adult life. I do 1 or 2 in the morning, another in the afternoon after I break my fast to stop the calorie/circadian rhythm "siesta" reflex I don't touch it after about 4pm though. Sleep like a brick.
Targeting caffeine is an ultimate "trees over forest" idea. If one is 7% and wants to be 5.5% and borderline dead, ok, I will listen....getting to more reasonable goals is about the macro. In this order:
1) No excess PUFA, no seed oils
2) Don't eat every 3 hours. Train at least the ability to fast.
3) Don't eat retarded food. If it requires a machine to do anything but slice it up, don't eat it.
Done. Just wrote my own diet book Good luck. Looks like you are kicking ass already!