[Jurri]

I don't think the heat-1 is a preference. It is a requirement, but it still causes the 5% income loss and related troubles. Just like with Abysia's humanbred theme and Jotun's Niefel theme: part of the cost is having to take an unpreferred temperature-scale.

You can try it if you don't believe me: take Marignon default with no scales and compare it to FoF Marignon with no scales aside from the required heat-1. You'll get 5% less income and 10% less supplies with the latter.