The would be several options to start from. But while having different ways at the get go when we close in to the end they become similar
First one would be an older detective, somewhere in his thirties. A lifetime of work in the industry having to find clues even where there are none has made him quite perceptive. Once mutated, he would become better at tracking people, finding clues and I would also go so far as adding lie detection. End game time would seem to slowdown while focusing, but even this cannot be kept up forever. Any distraction may pull him out of focus breaking his pace.
This character would be on the smart side playing it safe-er. In the end he would become a poor Bruce Wayne...none of the gadgets, some combat training(unfair advantage against the so called cannon fodder.) and a rundown car to provide transport
The second would be a young free climber. This discipline requires a keen mind as well as a trained body. Finding the fastest route and being able to pull it off is quite difficult. This character would turn to parkour early in the story since climbing seems to static for him. "If you can see the end, I ain't interested". His power development would be more inclined on movement facilitating. From the things that he dose not find interesting momentarily the color would fade out. Making his place of interest more visible, he won't see glowy stuff as in games thou...his reckless way of life spills over in his eventual combat.
Similar to the detective, his sight aids him in tracking people and spotting objects. Towards the end of both their developement the battle nature of this ability becomes more noticeable. Focusing to turn the battle in their favor by dodging and countering, but being on the edge where any hit may loose them their fight.