I didnt like the controls for SA, I think for SS they should do this, atleast as an option.
Classic:
W,A,S,D; Movement
Mouse: Aiming
Left Mouse Click: Fire
Right Mouse Click: Throw Grenade
Both Mouse Click: Charge (PP and BS only)
F: Melee
E: Use/ Reload/ Pick Up Weapon/ Enter Vehicle
Tab: Switch Weapon
G: Switch Grenade
Q: Use Armor Ability
This is the control scheme for Halo PC, and as you can see the Melee button is now closer to WASD,