Well, using a higher voltage supply will allow you to create strings, or longer strings of LEDs that can all be controlled with a single pin on a ws2801 or microcontroller. If you plan to setup your project so that each LED is controlled individually, I do not see any reason why you would need anymore than 5V.
Creating small strings of LEDs would be advantageous in that you could control groups at a time, and would require less memory to map. This of course would reduce the resolution and may not allow you to get that 'smooth' transition or ripple to travel around the blade. This is your call
As far as the LED being used on a 90 degree angle; I have only ever seen 3mm LEDs in a little plastic holder that hold them at 90 degrees. Others may have a solution for you, but my first thought is using a 45 degree angle on the inside edge of the outer-ring light-pipe to hopefully reflect the light outward. (I have very little experience with light-pipes though.)
Remember too that bumping up the voltage will limit the amount of current you can draw which is going to be important for many LEDs. Especially if they need to be individually controlled they will need to be powered in parallel.
Creating small strings of LEDs would be advantageous in that you could control groups at a time, and would require less memory to map. This of course would reduce the resolution and may not allow you to get that 'smooth' transition or ripple to travel around the blade. This is your call
As far as the LED being used on a 90 degree angle; I have only ever seen 3mm LEDs in a little plastic holder that hold them at 90 degrees. Others may have a solution for you, but my first thought is using a 45 degree angle on the inside edge of the outer-ring light-pipe to hopefully reflect the light outward. (I have very little experience with light-pipes though.)
Remember too that bumping up the voltage will limit the amount of current you can draw which is going to be important for many LEDs. Especially if they need to be individually controlled they will need to be powered in parallel.