-I am not familiar with many departments that paint ground ladders, especially if they are using aluminum ladders. Generally speaking it is usually wooden ground ladders that are painted and that is, in fact, what the NFPA standard was referencing.
-Moreover, painting ladders is much like painting a hand tool; it covers up and potentially hides any imperfections or problems/defects that have developed with the ladder.
-If you are truly seeking to improve the visibility of the top end of the ladder I would suggest using one inch reflective tape placed on the back side of the beams, nothing more. Painting aluminum ladders is inappropriate.

Good day...To add some Valuable incite I received many years ago..How do ONE insure that the DAWGS, are locked and loaded when we raise our ladders into place..A Wily Old Truck Veteran told me to place REFLECTIVE TAPE on the plates of the inside of the DAWG Covers.. Using your Flashlight in that Dark Alley in the Rear.. You can quickly spot those DAWGS and make sure that they are in place and locked..

We dont paint the tips however have looked at putting some type of relection tape on them. More so for our extions that would rise above the roof.

As for the middle point thats a great idea as we use our ladders as staging for our vent and RIT ops we carry all the equipment on them to the are of use.