Great idea, I've been wanting another option instead of the perfect neutrino detector. Personally, I enjoy a challenge and higher difficulty in my runs and using only the tools available in vanilla is just tedious, but being aware of all objects in hyperspace and system instantly, in real time, and with no cost or drawback feels unbalanced and goes against the spirit of the challenge. My suggestions are:
1. As someone previously mentioned, change the ability from an inactive passive ability to an active ability like the sensor pulse.
2. Add a volatile cost per activation balanced around the expected volatile cost of using a neutrino detector to fully explore the average system. Estimating that average is probably impractical, so let's say 10 or 20 volatiles (or a configurable amount) per activation.
3. Magnify the sensor profile of the fleet like the sensor pulse and neutrino detector do. If a volatile cost is implemented, the sensor profile could be boosted X times, with X being the volatile cost.
4. In hyperspace, limit the range to a fixed value or value dependent on sensor strength. An unbound range like it currently functions returns a truncated list of the multitude of warning beacons and derelict ships when in hyperspace.
Great work!