Does anyone else think Master Chief should have in-game quips in response to certain player-driven events? Such as when you attach a plasma grenade to an enemy, Master Chief will say "now that's what I call a sticky situation." Or "that's what I call sticking it to the enemy." Or when you shoot the Needler, he can say something like, "let me give you a few pointers."
To go even further, have Chief makes these quips during dramatic points during cutscenes. A perfect example is in Halo 2 when he jumps in the Covenant spaceship, detonates a bomb, and crash lands on a human ship, to which Johnson says, "for a brick, he flew pretty good!" After hearing this, Master Chief could say something like, "that was a blast."
I really think it could give Master Chief some extra personality. He'd be the natural evolution of '80s action movie stars.