I would much prefer a vision and "radar" system, so everything has a smaller vision radius but a larger radar raduis.
This opens the possiblity of two sensor branches in the tech tree and some interesting counters like jamming, stealth and cloaking.
Radar would only give vague information about what is detected like there is a planet but you don't know the class/other information or resources but not their type and starbases/precursor artifacts and ships/fleets with an rough indicator for fleet size based on logistics.
This could be improved via research additional to the range.
When something is revaled by vision it works like it does now.
Jamming could be shown via a static noise field in the radar range. So you know it's origin but not what's inside the field.
Stealth could reduce the fleet size indicator or maybe even completly hide the fleet from radar(I would advise against the later as it causes too many problems). Maybe scale the mass cost based on ship class, so bigger ships need to invest more mass for better stealth.
These two would have no influence on information gathered by vision but cloaking would hide your ships from visual identification but not from radar, so they are still displayed with the size indicator when they enter vision radius.
It would also be cool to have dynamicly blocked vision/radar, so you can't get intel on what's behind a nebula/ion storm or whatever but that would probably be to intensive in terms of calculations.
