What is the best damage type to both deal and be resistant to?

For example force damage is the best offensive type in the game due to lack of resistance, but one of the weaker types defensively as almost no enemies deal it.

Poison is one of the best damage types defensively due to how common it is on enemies, but one of the weaker ones offensively due to how many creatures resist it.

Which damage type hits that sweet spot, where there are enough creatures that don't resist it, but deal it frequently enough that having resistance to it will be regularly useful?