Best ET is always launch 3-400 RPM shy of peak torque, and shift 2-300 RPM after peak power. Torque gets you moving, HP pulls you out the top end of the track. No need to spin it to the moon, since anything beyond peak HP is all down hill anyway.
Just to put this out there but my 2000 was launched on the stock rev limiter with the stock rear end for close to a year (about 150 passes) before I broke the spider gears in the differential. That was with a few bolt ons and gears. Beating on the stock rear end is a gamble I've personally witnessed stock Mustangs with Nitto Dr's break axles on their first pass and guys launch on the limiter such as myself and go many passes before breaking.
My opinion is be ready for it to break. If it does then build it better, if it doesn't then you have more time to save money for better parts.