After completing Halo 4, I thought I'd go back and have a quick go at both KZ2 and KZ3 to see how they compare. Realised when played back to back, KZ3 is actually far better looking. Much more detail, better lighting, more post processing, effects, textures, texture methods etc. The AA implementation in a couple of levels is a bit iffy, but otherwise the game is ridiculously detailed, much more so than KZ2 and Halo 4 imo.
The scale in no 3's campaign is also actually bigger than I realised or remembered. Main two things I've noticed I really do miss from KZ2 however, the excessive motion blur (please bring it back GG!) and lastly, blood clouds. When you shot someone up close with an assault rifle etc in KZ2, as well as the splatters, dust, bits etc, you'd get like a plume of bloody looking gas. This seems to be gone or toned down severely in KZ3, unless you're using certain weapons. I miss it, definitely adds to the satisfaction of close quarters kills.
So yea, more motion blur and blood plumes/sprays. Bring em back!