Also, how long would it take 1000 pilots all lined up at the optimal distance apart take to search a planet?
This is a much better question than the "answers" in the OP. There is a distance when the ruins become "impossible" to see due to the smudge effect added to them in 2.2, but that's not the most efficient way to find them. The most efficient way is by sound, because its sound is very specific and you can hear it between 7 and 10km out depending on the situation.
Given a distance of 8km, which is feasible, the math becomes totally different to the OP.
Also, how many of those landable bodies are actually the same size as Earth? The one I picked to search for a bit (D101 C 3 A) has a radius of 655km, while Earth has a radius of 6371km. That's 5,391,290km
2 vs 510,064,000km
2, so basically 1/100th the area.
Given an audible/visual range of 8km to either side, every cmdr can search 3200km
2/hr. It will take one single cmdr 1684,8hrs (70,2days) to fully search that moon. Get together a search party of 1000cmdrs and it will take 1,7hrs to do it.
This is silly math though, as it's a sphere. Place one cmdr on every other degree on that planet, and send them North to south following the 180 line. At the furthest they will be 22km apart at the equator of that planet, leaving a gap of about 5km that isn't covered. That is easily covered by those that aren't needed near the poles, since the degrees are closer there. The circumference of the planet is 4115km, which means 180 cmdrs flying at 200km/hr can do it in just about 20hrs. A lot less if they are efficient.
Conlusion; math will be math, and searching 74 planets is a time-sink no matter how you look at it.