I'd keep the stock thermostat and upgrade the cooling system. A 160*F thermostat won't keep it from overheating, it'll just take longer to warm up.
At 160*F the rings aren't fully expanded and sealing, the oil isn't retaining enough heat to burn out contaminants, and you're losing more heat energy from the cylinders into the cooling system. With the coolant temp at 160-170*F, the oil is only at 200-210*F (typically) which means it's not hot enough to burn out any condensation in the crankcase. This was a common problem with older cars that ran the 160*F stats all the time. You need above 212*F to burn out condensation. I like cruising oil temps between 215-230*F, around town at 230-250*F, and spirited/racing at 250-280*F. Hot oil is clean oil is happy oil. The lower temp stat also reduces combustion temps in the cylinders since more heat is being transferred out. This is lost heat energy that would otherwise be pushing the piston down the bore. This is the same way that aluminum heads make less power vs iron heads due to the aluminum pulling more heat out of the cylinders. (Everything else equal)
Keep the factory thermostat and upgrade the fan. I don't like mechanical fans. They rob too much power and don't cool as good as even a middle of the road electric fan.
1993 Camaro bracket car
2002 Tahoe family/tow rig
2006 Altima daily