Started a book long time ago about "new man" or "new men" attacking regular human settlements far from Earth but can't remember the title and didn't finish the book. The main character in military and might be half man and his direct superior suspects and recruited him on purpose as he/she needs his special abilities or insights to figure out or fight the new men. A fleet is sent to investigate the attacks but is wiped out expect for one person who the main character recruits for his mission. Only got a few chapters in so I might be missing major plot points.
This might be Vaughn Heppner's The Lost Starship.
Ten thousand years ago, a single alien super-ship survived a desperate battle. The vessel's dying crew set the AI on automatic to defend the smashed rubble of their planet. Legend has it the faithful ship continues to patrol the empty battlefield, obeying its last order throughout the lonely centuries.
In the here and now, Earth needs a miracle. Out of the Beyond invade the New Men, stronger, faster and smarter than the old. Their superior warships and advanced technology destroy every fleet sent to stop them. Their spies have infiltrated the government and traitors plague Earth’s military.
Captain Maddox of Star Watch Intelligence wonders if the ancient legend could be true. Would such an old starship be able to face the technology of the New Men?
On the run from killers, Maddox searches for a group of talented misfits. He seeks Keith Maker, a drunken ex-strikefighter ace, Doctor Dana Rich the clone thief stuck on a prison planet and Lieutenant Valerie Noonan, the only person to have faced the New Men in battle and survived to tell about it.
Maddox has to find a place hidden in the Beyond and bring back a ship no one can enter. If he fails, the New Men will replace the old. If he succeeds, humanity might just have a fighting chance…
Maddox is half New Man. From the book:
Yet, what other explanation is there? What has the highest probability? That I’m a half-breed: a genetic experiment that got away from the New Men.