Werner's message here on footnote spacing has reminded me of something I sometimes wish I had in LilyPond: endnotes.
Whereas footnotes are printed at the base of each page, endnotes would appear in a block at the end of the score by default, with \pageBreak optional. Also, their appearance could be delayed so as to accommodate multi-movement works or even whole volumes without interruption.
There could be dozens or even hundreds of endnotes and so, like the ToC, the endnote block would spill over to subsequent pages gracefully.
I see Urs commented on the possibility in relation to ScholarLY here:
Is there any current interest from the LilyPond userbase?