I've been meaning to reply to this thread for ages.
On the topic of Far Cry 2-esq shooters, the first games that comes to mind (for me, at least) are Xenus 1 & 2.
Xenus 1 in particular (known as Boiling Point: Road to Hell in America) predated Far Cry 2 by a whopping three years and even predated STALKER by two years! It was the first major FPS to come out of Ukraine, and its developer, Deep Shadows, was actually formed of former members of GSC Game World, who presumably left GSC after Oblivion Lost got cancelled (that's just my hunch). So, if you like STALKER, then you should definitely try the Xenus games. Xenus 1 AKA Boiling Point was WAY ahead of its time. While it might be easy for some to laugh at its plethora of bugs, copy-pasted feel, and low-quality voice acting, it still offered everything Far Cry 2 did, and then some, despite beating it to store shelves by three years. Not only did Boiling Point have the benefit of being optimized specifically for the more powerful PC platform, but it also offered far more modes of transportation, most notably helicopters and planes, as well as easily twice as many varieties of automobiles for the player to drive. Also, Boiling Point feels like a true survival sim/immersive sim compared to Far Cry 2, because it takes limb damage into account (a la Deus Ex), which affects your movement speed, jump height, ability to aim, driving ability, etc., and features three separate diseases for the player to manage compared to just malaria in FC2. Oh, and the best part about Boiling Point compared to other open world FPS? The sheer size of the game world. Boiling Point's game world is over five times the size of FC2's, and while some of it does feel copy-pasted, it still allows for a LOT more space to move around in as well as helping the feeling of being immersed in an open-world survival sim. Not only that, but it also features copious amounts of civilians and hazardous wildlife, in case you get bored and want to go on a shooting spree GTA-style or go poaching for jaguars in the jungle. Oh, and Boiling Point even features Crysis-style interactive physics; the urban areas are bulging with household appliances and street clutter for the player to pick out and hurl around at wherever they want. You won't make many friends this way, though, because the game features 7 different factions for the player to work with, all of which dynamically shift their attitude towards you depending on whether you do good or bad things to them or their allies. For example, the bandits are fiends with the Colombian mafia, the Guerrilla army hates the government, and so on. And that's just the tip of the iceberg with Boiling Point. There's so much more to the gameplay mechanics.
However, despite all of the stuff that Boiling Point offers over Far Cry 2, I still think Far Cry 2 is definitely the better game of the two. The thing that Boiling Point really lacks is polish, especially in regards to the NPC/enemy AI, which is why Far Cry 2 totally blows Boiling Point out of the water when it comes to the actual combat. The enemies in FC 2 are just so much more enjoyable to fight because of how much more detailed & smarter their AI and pathfinding is. Boiling Point's AI feels so primitive by comparison, although considering the sheer amount of variety and freedom the game offered for the time it was released, I think this is excusable. Still, it does make the experience feel rather dated. Far Cry 2 also features ragdolls, where as Boiling Point does not (Xenus 2 does, however).
I haven't played Xenus 2 yet so I can't comment on that one, but you can bet your garters I plan on buying it as soon as I have the dough. Plus, unlike Boiling Point, Xenus 2 is available on Steam, whereas Boiling Point/Xenus 1 is, tragically, not. In fact, Xenus 1 isn't available on any other digital distribution platforms at the moment, either. But the good news is that the physical copy for Boiling Point still functions near-flawlessly on modern Windows (Windows 10 at least; I haven't tried my disc on a Windows 7 or 8 rig, yet). The DRM for the American release isn't a problem, either, although I've heard that some versions of the European release have the dreaded kiss-of-death Starforce DRM so if you're in Europe I would simply recommend downloading the ISO off of an abandonware site like My Abandonware for safe measure.
So yeah, Xenus 1 & 2 are definitely worth looking into if you're a hardcore fan of FC2 and want to try something similar.