Do like most of us do. PL5 from race start and look how quickly temperatures increase then adjust to make it stable. Formation lap doesn't add any value to the game. The race starts when it starts (not when formation laps happen).
But why not make look for like a real race rather than simulated.
I get if you did a formation lap that maybe was all just a pre race animation you could watch. But other than that it adds nothing. Otherwise you’d have to add things like tire and engine wear. Just not necessary.
But you’ve got that anyway