Next Apple Pencil may have interchangeable tips and an eraser
At least, that's what seems to be the case based on new Apple patent filings that show options coming for an Apple Pencil eraser as well as interchangeable nibs. The US Patent and Trademark Office has decided that pencils never had erasers, calligraphy sets never existed with changeable nibs, and the Microsoft Surface Pen also had no eraser option, and granted the patents to Apple. As always, well done on not understanding your only job, USPTO.
If Apple were to institute all of the features in the patents, the various nibs would range from standard tips like a felt-tip pen, to more complex options like a force-sensing bristle brush tip or even a motion-tracking camera. The patents also mention the possibility of adding Touch ID to the Pencil, presumably so you can unlock your device just by picking up the Pencil (and also so the device can "justify" its cost?)
Since these are just patents, there's no guarantee if or when the changes will come. We'd assume the eraser feature will be in the next Pencil at the least, but the other options are less likely.