How fancy of a Thermostat do I really need?

Because a t-stat is the single most IMPORTANT piece of equipment you will ever buy, I would suggest a reliable thermostat.

Helix have a great reputation so do Herpstat.

I run everything from racks to incubators with Herpstat some are 8 years old and still working great.

I have a bunch of the dual zone Vivarium Electronic ones. I also have one Herpstat that came with my incubator. It's the basic herpstat model.

Both brands work very well for me. If you get a VE or a Herpstat you can't go wrong, IMO.