A 78-- or LM317 are for 1A or a little more and they get hot, you might need a heatsink.
A DC-DC converter is very efficient.
Do you use an Arduino and a motor driver ?
If the servos are 6V, you could use a DC-DC converter to 6V and use it for the adapter plug (or Vin) of the Arduino and the servos.
If you can power the leds with 12V or a with second DC-DC converter, you would only need a power supply of 12V.