"biotech for superhuman soldiers"
So, if we're talking biotechm we're not talking about exoskeletons. We are thus still limited by what the human can do. There will be no biotech that will allow a human being to jump over a 2 meter wall.
If you start mentioning nanobots, we're off to sci-fi land and you are irrelevant. And no, we're not going to be modifying eyeballs to have Terminator-style Augmented Reality screens inside our heads. So what's left ? What are the domains were biotech would actually bring something to the battlefield ?
I'm guessing that one area that would bring certain benefit is if soldiers could recuperate faster. Sprint over 50 meters, recover in three seconds, dash again, repeat five times. That would allow for much faster covering of territory, quicker repositioning on the battlefield and thus more effective use of firepower to take the day. At least, I think it would.
Another area is enhanced awareness, ie sleepless soldiers. That is an area that has already been studied for decades and we're no closer to any real solution. A soldier that is awake for over 48 hours at a stretch is a soldier that starts losing his grip on reality, no drug has been able to correct that. So I don't know that there is any biotech that can correct that issue, but that would be one hell of an improvement on the battlefield. Combined with fast recovery and you have an assault force that could fight for two days straight and litterally wear the enemy out before reinforcements could arrive, thus vastly improving battlefield results.
But I don't see that biotech will enable soldiers to shoot better, or see at night, or run faster or carry heavier loads. Equipment and training help for those things, not biology.
So what biotech is being cooked up in the secret labs ?