Recommend you first read this thread:
It contains my assessment of how to use Drafts for a Zettelkasten (a system of linked notes). In the thread I list a set of actions (available in the Drafts Directory) that I think are needed for this purpose.
With respect to links based on headings. There is currently (to my knowledge) no way to link to a heading - versus to the title. I agree that being able to do so would be a valuable enhancement to the current Drafts capability.
With that said, this method may provide a work-around:
Construct a heading using a UID, with the UID coming first or last. For example:
## 202008290319 My Heading
Then use a search link to the UID:
[[s:202008290319]]