linkPrev and linkNext need to return the linked element, so that the calls can be chained to form a linked list.
More generally, they need to insert a full set of already-adjacent elements and return the farthest element.
It would also be useful if elements tracked their parent elements, so that these methods can update a parent list if not top-level.
Methods for analysing number precision are not yet released.
Methods for handling an element as raw bytes are not yet released.
Where adjacent elements are handled optionally, review the boolean argument names.
The names "adjacent"/"adjacents" could be better if renamed to "topLevel" or similar.
Markup page
Content type description/example for bools, numbers, lists, pointers.
Feature description/example for classes, templates, includes, as-above.