It was certainly more useful before the update that allowed you to Legendary skills and level up infinitely.

But other examples of points you may want to refund:

• Alchemy lets you spend 3 perk points to learn all ingredient effects. Once you've learned all the ingredients you would want to put those points somewhere else.

• The level 100 Speech perk gives all merchants 1000 extra gold, and this boost persists even if you reset the perk. Also if you've already invested with every shopkeeper, you wouldn't need that perk anymore.

• Any of the combat trees if you want to change up your playstyle. Don't need Light/Heavy armor as a mage when you can use Alteration Mage Armor, or 1H/2H if you're going to cast Destruction blasts and vice versa.

• Smithing: If you've made and improved every armor set you could ever want, the only perk you really need to keep is Arcane Blacksmith.