When you want power, then you need power. At the start, you typically won't rev hard until the card goes sideways. After that most starters drop the gate in 3-5 seconds. That is not a long time to be on the limiter. If you just dump the clutch, then you will more than likely find yourself picking you bike back up less than 20 feet out, you have to release the clutch smoothly, fast enough to rip out of the gate, but slowly enough to keep the front wheel within a few inches of the ground.
There is a lot more to a good start that this. For a first race, you probalby shouldn't even try for the holeshot, that first turn is a killer.