I like the first part better without the percussion, I'll say.
Fun fact though - That percussion loop in "Overture" from Reach (the main menu) is from EastWest's library "Stormdrum". I've heard it in an episode of Nova, two episodes of Survivorman, some random TV action/drama show that was on when I walked through the living room once, and in a track from COD4 Modern Warfare.
Don't believe me?
Listen to this track from COD4.
Also, to add - I recently got Native Instruments Evolve Mutations as a graduation gift. When going through the sounds, I found 2 loops and one cinematic hit sound that Kazuma Jinnouchi used in his work on the Halo 4 soundtrack. I used one of those sounds in my Halo 5 Fan made theme I posted... tricks of the trade, man. I love coming across sounds that I've heard before in popular music.