Actually, I would go 4.10's, lca's, then shifter. With the excess accelaration you get from the 4.10's, you need to be able to plant the tires more than get an extra tenth from the shifter. But shifter and lca's together are cheaper than gears + install. so get 4.10s, then next round, get shifter AND lca's.
gear will make for faster acceleration, the LCAs will help with traction, and the shifter helps a little, but the least of your list. it is nice to have a shifter though. knowing you are in gear is a good feeling. i thought the stocker was pretty good too. i never missed a gear at the track with it. (of course i dont have 500 rwhp, so i dont have many problems with my shifts. )