I don't really understand
Nor will you by the sounds of it, but here it goes anyway.
It sounds, to my ears, like you want to play the game with weird variant rules and alternative scenarios but not unless GW tells you to.
I'm talking about rekindling something GW has already done because I liked the idea. I've always wanted to update the Last Chancers to something that could work within the parameters of 7th edition, this looked like it had the opportunity to be a Deathwatch version of that idea without me having to make a ton of stuff up. The lack of specific Detachment doesn't slow me down, it just means that there's more stuff to make up and as such more stuff to explain and workshop with opponents before we play. If there was a Detachment (FOC style, not a Formation) that had some unique Command Benefits or Special Rules it could potentially be a much easier sell to use in said mission and let the mission special rules work to balance the otherwise hilariously one-sided match. Ultimately the Detachment is not necessary for my plan, I just wish there was one.
Honestly I think that if you knew what I was referencing initially you wouldn't be confused. The fact that you have/had no idea how the Last Chancers were introduced to the game is a serious impediment to your understanding of my concept; I am not talking about playing the game the way you have grown up understanding it despite using the same rules for gameplay. Ever seen the movie The Dirty Dozen
Granted they're not the most balanced unit internally, but they are not without uses.
Good luck with that view in this thread