Iam a huge openworld Rpg fan, my favorite games are: Fallout 3/NV, Skyrim, Risen1 & 2, Mass Effect, Gothic 2, Rage, BioShock, Assassin's Creed, Metro.....
I mostly play MMORPG, so Lineage II was my life-eater back in university. World of Tanks and Warthunder were doing the same until recently. AC3 and 4 do it now. Many new great games are coming, but mostly on consoles, so I have to wait for them being ported to PC... sigh... Space Rangers 1,2 ; Fallout 2, 3; Warhammer 40k series, Starcraft 2 series - these are all magnificent. As for CoD - gameplay, HUD, AI and graphics have not changed since part 3: MW, all the rest are just clones... dropped it.
Need for speed underground & Need for speed most wanted Call Of Duty 2 Counter Strike Red Alert 2 GTA 2 Bomber Man
without getting too nostalgic Age of empires Rollercoaster Tycoon C&C Red Alert 2 + Yuri's revenge CS 1.5/6/source MOHAA AVP back in the day Black hawk down Diablo 2 + LOD (current) WoW (on & off until new expac) Diablo 3 and of course the latest DayZ standalone which i might as well say is awesome. by far the