There are several obvious answers:
- Batman - since there's an option in the game to create non-powered investigators in the Heightened Crimes division, I think building a low-powered Batman analogue is pretty easy given the game emphasis on investigation. He may not be a master of the fighting arts, but he'll be a master detective with some skills in hand-to-hand. Investigational emphasis would be a jack of all trades investigator, plus the patented intimidation skills.
- The Elongated Man - an unusual choice for powers, but one that would work well with the Batman analogue. He'd be less driven, less serious, but certainly share in that passion for solving crimes. His powers would be limited to the stretching of limbs, and I have to check the Quade Diagram to see what his twitching nose might be defined as.
- Jonni Thunder - so she was a private eye, but she tended to rely on her detective skills rather than her Thunderbolt persona. The Thunderbolt abilities seemed to be limited to flying and blasting people with energy, so that should be doable.
- Wolverine - well, he has a reputation as a tracker, so that would be his specialty. I'd have to figure out how expensive his animal senses + healing + claws would be. Sorry, no adamantium.
- Daredevil - doesn't have much of a reputation for actual detective work, but certainly takes the cake for enhanced senses. It'll probably be too expensive to get all the enhanced senses -- the supersensitive touch in particular is too far away on the Quade Diagram -- but we'll approximate the best we can.
- Chameleon Boy - from the Legion of Super-Heroes, Reep Daggle had a skill in this type of thing, especially as a member of the Legion Espionage Squad