You forgot: 4) Increase/decrease the blood flow towards our skin and arms/legs. This is why in hot conditions, blood vessels may widen, the heart pumps harder

You forgot: 4) Increase/decrease the blood flow towards our skin and arms/legs. This is why in hot conditions, blood vessels may widen, the heart pumps harder to increase core <-> skin heat exchange, and you see people blushing. In turn, this "heart pumps harder" (or failing to do so) may worsen other conditions (especially in older people), and eg. contribute to kidney failure (and that in turn, to blood poisoning).