STALKER, just playing it through again slowly with the mod linked above. The only thing that combo mod doesn't have which I'd like to have seen is the mod that gave the NPCs the ability to loot corpses or pickup items they find, which is a shame as that sounds immersive, but the mod really adds to STALKER in it's own way, as it's a pack of some of the best upgrades and tweaks, I still need to check the mods menu actually.
Tis a little buggy, and save often as it's hard near the beginning with that mod (H&K > merc suit

) but its got a great atmosphere, for example I was just wandering around at night, and suddenly had to hide (stop moving, light off, no noise etc) as a patrol party of bandits ran past (about 10 of em) and began battle royale'ing with a party of stalkers camped in the scrap yard... which if I manage to survive after work I'll be running to loot the corpses

Silenced pistolling and surviving the entire military patrol at the bridge near the beginning was tense too, luckily as I was moving slowly they weren't 100% were I was and I managed to get em all and nick all thier stuff
Awesome game, if you can get into it.