It definitely is broad enough to be used in creative ways but I'd never say it was different for everyone. The first time we got to experience Haki as the characters do was through Usopp, our Everyman who we can all relate to. Within the same arc we get almost the exact same visual with Fujitora. It was exactly as Rayleigh explained, the thing about even invisible enemies can be seen through observation. Predicting movements was done by all the higher ups of Eneru's group as well as the Boa Sisters, Ray, Luffy, etc. Usopp will most likely develop his ability to predict movements as time goes on.
I didn't explain it too clearly in my previous post, but I didn't mean Haki was completely different for everyone; how Haki manifests is based on the person's proficiency and fighting style. IMO, Usopp being able to see exactly where Sugar and Luffy/Law was is a higher level of CoO than the spider-sense type, but Usopp has never shown any sign of that spider-sense feeling that I can remember. He went straight to the thermal, as it applies greatly to his fighting style. Robin, on the other hand, showed signs of that spider-sense when Hakuba went after her. I doubt she can do what Usopp can do (yet) though. Both are CoO but one is more effective for Usopp's style, the other is more effective for Robin's style.
I agree that Usopp will most likely develop the ability to predict moves and that will also help with his sniping. I don't know if Robin ever will, though.
If everyone was to train the exact same way, there's no question they'd all develop the same way of using CoO (and CoA), but clearly, that's not the case. Everyone has the capability to do everything possible under the CoO umbrella, but that doesn't mean they'll learn every bit to CoO.
I hope I make better sense now.