Beautifull creation!
It seems that I get somewhat better heat tolerance by tinkering (upwards) with the Coolant pump value.
It still overheats above 5-5.5, it takes just a bit longer, but the downside is more dead load (less SWs delivered)
so we might avoid an overheat on cold(er) environments
(form tested x/10-0.4, clamped between 0.1and 0.8)