Even in your Thing example, there are lots of situations where a 3x multiplier would win him the day. Wonder Man, dehydrated Namor, She Hulk, Captain Britain, Titania etc are all now characters he can defeat or at the very least has MUCH greater odds of doing so.

So yes. 3x is not 10x or whatever constitutes an order of magnitude, yet low and behold it makes an appreciable difference to who wins or not, even in your own example.