There is not a problem seeing objects in the dark. As I mentioned I saw my MP 2.5 km away with a very cheap torch attached bought fro a local hardware store.
Flying in the dark can be fun but the challenge is to see it in daylight. All drone flyers have the same problem, they fly at a distance look at their r/c and they lose the craft. Then you have to bring it back a bit and start again. This is the only time I use the RTH. I suspect a lot of us do. This is because we don't know where it is.
The issue is much improved with the BT glasses because your time/distance from looking at the r/c display is a few mm away not many cm. Yes in ideal conditions you can see through the glasses, never at a distance though.
So we need a short term solution to see our craft at a distance and quickly find it every time if we blink or look away.
The long term solution, as I mentioned, is an augmented construction of the craft generated by multiple sources of data.
Drone developers really need to start adopting the approach manned aircraft designers/constructers use.
Follow the same conventions of bright visible lights and the same colour orientation codes.
No one has a problem seeing the smallest manned aircraft in the sky. And I am sure they have thought about it but the power needed is a serious challenge to battery energy.
However this is not now a real issue. It is not an excuse to say it takes too much power from the flight time.
At first I thought it all a matter of the amount of lumens. This is not true. Its how you use the lumens, the kind of material the direction of the light the kind/colour of light.
I can see a very cheap torch at 200 lumens better than a relatively expensive cube at 1,500 lumens. And the torch lasts for 4 hours via a usb charge, as is the Cube. The Cube lost power after less than 20 minutes. There are ten levels with the cube. Oh its also a lot heavier and very ugly standing high while I tape the low lying cheap torch, about the size of a quiet small lighter.
Its not about muscle its about intelligence.
lannes makes an excellent point about red being easy to see in the day and pointed to a bike rear lights. That is a good place to start, as others have pointed out. After all bike light technology has had a lot more time and money dedicated to it than drone lights.
But so have manned aircraft.
We should not be having this discussion its so simple. Its a shame we have to sus it out companies like DJI should have sorted this out years ago.
So I bought a bright, red, cheap rear bike light and am going out now to try it out. I doubt it will work particularly well but plan b is to go to a local sports/camping store that I know sell quality bike lights. lannes bike example says it can be seen 2 km away. So we know its doable.
Plan c is to follow up on a quick search I did with the words "best visible red bike lights"
Interesting search.