The distances involved in the OFP/ArmA games make the enemies small. In that regard it is beneficial to have a high rendering resolution, but on modern systems it is like this: the rendering resolution should match the flatscreen resolution.

Some other things to enhance the graphics a little:
-When using nVidia or AMD graphics: enable at least 2x Full Scene Anti-Aliasing (FSAA 2x) in the graphics card control panel.
-Use this mod: https://forums.bistudio.com/topic/118723-ww4-modpack-25/

As to ArmA 2 and its CWR2 mod. I don't think the controls have improved or changed much. I am OK with them. The ArmA 2 game introduced ground clutter/grass and that may make enemies even harder to spot.
The CWR2 mod is a great mod AFAIK. The only risk of such mod is that the mission flow may not exactly go as intended, because the AI in ArmA 2 works different from the original CWA.

Hope this helps,
It was nice that CWA and ArmA 2 were available on GoG once, before they went almost enterily Steam exclusive.