In this case there will just be 1 set of LEDs. Some of the other projects will need multiple chanels but there will be 80 per chanel (maybe double that depending on the project).

So far ive always been planning for the LEDs to use 50mA to make sure i dont get a transformer thats too small. I know in practice that they use a little less.

Now for a dumb sounding question. How do i run the LEDs at 30mA instead of 50mA. Im lead to believe that if i use, for example, 5 LEDs on 12V instead of 4 then obviously the voltage drops but the current is supposed to drop too.