temp drops are important for good growth.
I would pick option 2. Maybe add a thermostat but that is optional.
I actually use 120watt tubular heaters. I know they are trickier to buy in the us but they are really cheap here and have a built in thermostat.
Amazon should sell them these days, they sell everything
edit: ok that is one thing amaz.com does not sell. Very strange, they are really safe too, doesn't make any sense
Nest best option is a heating cable then:
Amazon.com