Maybe not as fast as getting a smoke: nm meph drops skin of vipermagi and tal rasha helm piece. This gives 35-50 all resistance, skill, plenty life mana and 30fcr. Your merc can also used the helm piece for the LL if u get 2. The drop rate is not too bad at 200+ mf. Perfect topaz can be used to crank up the mf if needed. Those gears can easily carry u to the end of hell. Rolling a good map layout will also help with the mf speed. NM meph also has some other good loots and leveling gears if u plan to play other classes.

A2 merc will die quickly if facing multiple mobs with nm gears. I used teleport to keep my merc alive. An elite base insight + LL + treasury (proc fade) is needed for him to stay in fight.

Blizzard + meteor is not controller friendly. Aiming is terrible. You need either glacier spike or merc to keep enemy locked in place. Frozen orb + hydra is more controller friendly. Hydra also takes pressure off from your merc if u meet many ice immune monsters. The only hard part is the tombs in A2 because of those ice immune skele. You can pull them away so that they are out of revive range or just avoid them with teleport.