I have a WIP version of a reaper style jacket torsodeco designed to be worn over tshirts etc but it wasn't ready for release as had some major clipping issues, aiming to add it in a future update.

MrCloista, what you think about, Skrimishers boots, but with xcom/shanty pants variations?

I think that'll be a hell of a lot of kitbashing, assuming you mean the trouser part being shanty but then having the big clompy skirmisher boots. Maybe one day, certainly not soon.

Maybe modular advent armor meshed with civilian/xcom uniform pack?

Reaper style Jacket, but torso deco/shoulder is available?