So i was messing around with idea of enchaced guardsman for some time. I wanted to have some explanation why some particular can take special missions aka deathwatch style insted of just sending deathwatch. After some reading various books, supplements, codexes etc. i came with an idea inspired by Detachment D99 (special elysian force serving inquisition).
In my current campaing players after their former was almost wipe out (12 men survived) was drafted into inqusitorial special task unit called Gladius Veritatis. The unit was formed mostly from veteran cadians who fought chaos and tyranids. Inquisitor in charge with magos biologis developed experimental gene therapy which should enchance guardsman fighting capabilities so they can stand against xenos and chaos forces and do mission which are too much even for acolytes.
After messing up with rules i came up with something like this. A bunch of traits all which have some flaw.