One question that kind of got forgotten about was the current and amperage that the pushbuttons (that I would be replacing with toggle switches) operate at. Its very important to me that my LEDs are not too dull when they are connected.
The switch circuits on the shield operate at 5v. Current consumption is determined by the load (in this case the leds in your switch). Without any real specs on the switch it is hard to say. But from what we know, you are able to connect them between 5v and GND and not let the smoke out, so I'd assume that there must be some internal current limiting resistors to keep the current draw under about 20mA.