If you've already tried a bunch of different extremes, did you find that any of them worked or were relatively easy to incorporate into your daily "lifestyle"? Extreme stuff tends to maybe work for a while, but is mostly just becomes a pain in the ass to keep up - either thru getting sick of the food or having to gag it down, or it becomes inconvenient to your daily life - that stuff isn't maintainable because it is a pain in the ass, so usually better to find the more conservative thing that you can do consistently.
If you want to step back to the basics and evaluate what "works" and what doesn't - start by establishing a basic diet that meets your macro needs - e.g. 1.5-2 g of protein / your body wt, pick a decent macro breakdown like 40% protein / 40% carbs / 20% fats. Build out a meal plan that will meet that and then use it for a while. See if it is giving you enough energy for your training / good quality recovery and producing whatever result you are looking for. From that you may find that you want to throw in a protein shake 1/day to supplement your protein intake.
Beyond that, you can experiment w/ a couple supporting supplements - some basic stuff you could start evaluating:
- pre-workout. I used to LOOOOOVE my thermos, like back in the day when there were good products like Syntrax Adipokinetix, but in more recent years, I don't especially like the feeling of a thermo and it isn't something that I really care about "needing" to get a kick going into the gym. There are much better & more variety products out there these days. Go ahead and try one and see if you like it.
- BCAAs - I don't think you lose w/ these - esp if you train balls to the wall
- PWO shake - do you do this? Best time to replenish your glycogen is immediately (or within 30 min) workout. A lot of guys I know bring a shaker w/ their protein, glutamine + dry oats, add water & chug
- Creatine - sure, can't hurt - see if you notice a difference
- decent multivitamin & EFAs - I don't see a down side to this - do you know if your current diet is providing all the stuff that you'd want to support your daily life?
- fiber - keeps you regular - esp if you're pounding a lot of protein and maybe not eating a lot of veggies. (I find guys tend to hate veggies ...)
From there if you want to experiment w/ other stuff that comes out, go for it. I went thru that phase of my life 20 yrs ago, so I tend to keep things simple these days. Also note that if you're throwing in a bunch of different things at once, hard to really tell if any one thing is working better.