obstruction tough to see; shove a light on it.
a tower crane costs i should think upwards of of a couple of hundred thousand pounds.. a couple of hundred quid in lighting isn't going flatline the economy.
To be frank, I think that's counter-productive. What does one do presented with a light one wasn't expecting to see? Commonsense tells us we've not 'planned' or 'expected' to fly into a crane or a building! My reaction, and I'd guess, the instant reaction of an unexpected light is WTF!? If you check the rules, an instant response of up, down left or right isn't clear to the pilot. The marine cardinal system is better (but don't let's go there!) but still takes huge concentration to interpret from a pilot who is only in this pickle because something(s) else went wrong earlier.
Sir Humphrey Appleby would agree with you..."shove a light on it". Job, and jobs for lots of boys. But would it improve aviation safety?
I really don't know. It's a discussion but a discussion that needs a lot of thought and considered debate from experience people. At this stage I don't think we ought to 'shove' anything anywhere other than preconceptions and ancient rules in the melting pot.