It’s quite possible you don’t eat enough. My SO is shorter and lighter than you but he would be starving with only 2000 kcal. It may be enough for you, it’s individual but quite possibly not enough. it may be the reason for fatigue after feeling okay in the beginning when you had some more fat.
Not everyone get energy when they get fat adapted, the same is true for OMAD. I feel just the same, it’s merely convenient to eat only once (and avoiding eating too much) unless I can’t eat big enough meals at that time. I have lowish-energy (it seems it gets better on carnivore…? hard to tell as there are so many other factors and I go off a lot… but I never ever felt very energetic), keto and fat-adaptation didn’t change it. Similarly to you, fat adaptation changed my hunger and that’s it. These things are individual and anyway, we have different keto styles, our past matters too, different circumstances… Of course we can’t experience the same changes. My brain feels the same on every woe too, by the way.
Carbs: It’s individual too. Some people need to go as low as possible, some even need to be extremely low to get into ketosis though it’s not that common. Others feel way better with a bit more carbs. Experiment and figure out what works for you.
I personally couldn’t function with <20g net carbs only in the beginning, I couldn’t even eat that little when I touched vegs and nuts (and no meat, yeah, that wasn’t helpful. but I got fat adapted with 40g net carbs, mostly from plants too) - but I didn’t get any noticeable benefits beyond the cute soft fat-adaptation hunger either. Eventually I went lower and it got WAY better. Many people say the less carbs is the better for them. Or that total carbs matter, to me only non-animal net ones do as far as I can tell but that should be quite low.
So it’s simply impossible to say what rules you should follow…
A bit more protein wouldn’t hurt though…
Supplements are individual too, I use none and I notice no problems as long as I eat enough meat. But many people need them. Sodium is the interesting electrolyte that is all over the place, some people function best with a lot, others with none except what they get from their fresh meat (and hat’s very little)… And some of us need to stay far from both and have a moderate amount of it. I imagine some people are fine with almost whatever…
Your minerals must be fine, I would change the macros. More protein, maybe a bit more fat too, I have no idea if you would work better with more carbs, I would change fat and protein first. Just a little? Don’t you feel it would be nice to have more of them? I often have these nudges. More eggs, more meat, more fat, less fat. Useful.
If you don’t have extra fat, why on Earth do you keep an energy deficit?
I don’t know what to say about water, I just follow my thirst and it’s perfect for me. I surely go over 2 liters in summer though I can’t measure it. I am a quite thirsty type especially in summer or during any exercise. I still don’t need to supplement sodium but if I drank a really huge amount, I surely would need that, certain things are unavoidable.