Not sure where you get 2-way, a fender mounted fixture that can be seen from the front and the rear is a 4-way flashing light even if only 2 bulbs are involved.
Of course adding more lighting and brighter lighting allows you to see better and to be seen better, both play important parts in safety.
Also with the age of most of our machines, and the low amperage output of the dynos, the lower requirements of amperage for LEDs and the greater output are a win/win/win. With a bit of creativity, all of our old style bulbs and fixtures can be reworked to use LEDs that are now available.
If you can do some light duty electric work, you could do dual function LEDs for our blinkers, and add a circuit to the second element function (like a 3157) and have a blinker system and a flasher system.