- never use the benchmark, its ugly with my settings, beautiful in-game, check your FPS playing a quick custom battle with lots of troops
- check unlimited memory (here is why :
http://forums.totalwar.com/showthread.php/80298-Explanation-of-low-quality-visuals-and-the-new-%E2%80%9CUnlimited-Video-Memory%E2%80%9D-option?s=bd3cb1416b947deaf4af9e79c9d12b22)
- unit details on high; on higher settings the FPS drop a lot for not much graphical improvement
- 1st set of graphical options to tick off : V-sync, distortion effect, SSAO, Vignette, DRA, Anti-aliasing, vegetation alpha, depth of field
- 2nd set of graphical options to tick off/lower : shadows, water, sky, particle effects
- 3rd set of graphical options to lower : trees, grass, terrain, , texture filtering
Best cost-efficient option (to leave at high-extreme as much as possible) : texture quality, shader model, building details, unit details (high max)
Then Unit Size greatly amplify the settings you made, so you gotta choose if you want size over details before anything. Personally I barely have a taste for 160 men formations (god bless the 2x unit size mod) so I would have tried to make it happen even if I would have to look at zombies all the time.