The suit that I would use for a base assault would be either of the armors (Flak Armor or Kinetic Armor), and the Ammo Storage Canister. The Ammo Storage Canister is a good tool when assaulting a base because it may be a while before you can get to an equipment terminal to restock your ammo. This is a good reason to take the extra ammo, because it means you can fight longer without having to run back to base or find an engineer for ammo.
The weapon loadout I would choose for Base Assault is the Falcon/Scattercannon for New Conglomerate, M1 Heavy Cycler/M3 Punder HEG for Terran Republic, and the Comet/Quasar for Vanu Sovereignty. I would choose this loadout because it gives the MAX flexibility to fight effectively against either vehicles or infantry. In addition to this cert, I would take the Laser Sight cert and attach it to the rail of the weapon to increase accuracy when firing from the hip.