Aziz Bhatti Park, Safari Park, and Karachi University are three areas in relative proximity that are good spots for standalone run or can be combined for a longer run. The 8-acre Aziz Bhatti Park (Block 5) is nicely landscaped, features a small lake, and paths that make for a run of ~1 km. Then use University Rd., to connect to Safari Park (~2 km). It’s a wide road with decent sidewalks. Not scenic, but runnable!
In Safari Park (small admission fee required), there are a couple of paths that are popular for running, including a path that goes up a hill — one of the few spots for a hill run in Karachi! One could put together a couple of km here.
Adjacent to Safari Park, the NED University of Engineering and Technology and Karachi University have a sizeable campus. Put together a run on the numerous paths and fields.