I dont have military experience so I cant speak towards the diet, but overall I am not a fan of Keto diets myself. After you cut out carbs, in a couple of days you will get very debilitating headaches, this is because carbs are fuel for your brain. Without carbs, the brain cannot get food. While it is possible to use fat and protein to get this, your body has a much easier time to convert protein to brain energy than fat (and it leaves a toxin as a byproduct). In short, it is really for emergencies only. Overall, if you eat less than you use (hard to do) you will lose weight. Eat more and you will gain it.
As for your body fat, i guess I would say around 20%. But that is just a guess. If it makes you feel better, I have crazy high standards, and I would hit it.
Overall though, dont obsess over abs. They are generally worthless. Every hot chick I know tells me the same thing "Yea abs are nice, but there is nothing like a man who can pick you up during sex!" Work on that, the ladies will appreciate it more.
Hope that helps and thanks for the service!