I know that HolographicDisplays is in a state where it only receives required updates for compatibility with newer versions and suggestions are (more or less) not added.
But I still want to suggest this here since I thing people could need it in a way.

Idea

My idea is to add a way (subcommand?) to allow an empty line in hd.
Right now you can't have an empty line. At least not in an easy way.

By empty Line I don't mean like a line with no text in it. I mean a gab where no text is, because just having an empty line still leaves this semi-transparent background of the nametag that can be annoying.
So an option to have a small gap between two lines would be cool to have because the only real way to have this is by having two separate holograms.

Possible ways

One way could be an additional command like /hd addblank <name> (and of course the other variants of it like setblank, insertblank, etc.)
The second idea would be a sort of placeholder like {blank} that tells HD to just move down x units without adding a text. This solution could be more useful because that way you wouldn't need to add separate sub-commands and editing could perhaps be easier.

you could do &r so it will be blank, or in the database.yml
- ''
will do it

Like I mentioned would this still keep the tag itself

the
- ''
wont

Hi, there's already {empty}, the tag is not visible.