Temperature differences only affect when switching off, engine cooling time (1 min in summer, 2 min in winter). When starting up, whether it's summer or winter, we have the same parameter values, the procedure is the same. 20% of engine speed, the rotor starts. And that's enough for me, and how fast it spins up... At the moment of start it will definitely be good.
There are a few little things that could be added to make it even more realistic, but they would not affect the gameplay in any way. Let's not forget that DCS is a battlefield simulator where we focus on something else.
One thing I would like to see more refined is Petrovitch. Most of the time it's just additional ballast, and it could, for example, help with navigation or be more active in detecting targets.